[d2b2a7] | 1 | // $Id: deform.lib,v 1.10 1998-05-05 11:55:22 krueger Exp $ |
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[f0c6f4] | 2 | // author: Bernd Martin email: martin@math.tu-cottbus.de |
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| 3 | //(bm, last modified 4/98) |
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[3d124a7] | 4 | /////////////////////////////////////////////////////////////////////////////// |
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[d2b2a7] | 5 | version="$Id: deform.lib,v 1.10 1998-05-05 11:55:22 krueger Exp $"; |
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[5480da] | 6 | info=" |
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[f1201a] | 7 | LIBRARY: deform.lib PROCEDURES FOR COMPUTING MINIVERSAL DEFORMATION |
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[f0c6f4] | 8 | by Bernd Martin (martin@math.tu-cottbus.de) |
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| 9 | |
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| 10 | versal(Fo[,d,any]) miniversal deformation of isolated singularity Fo |
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| 11 | mod_versal(Mo,I,[,d,any]) miniversal deformation of module Mo modulo ideal I |
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| 12 | lift_kbase(N,M); lifting N into standard kbase of M |
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| 13 | lift_rel_kb(N,M[,kbM,p]) relative lifting N into a kbase of M |
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| 14 | kill_rings([\"prefix\"]) kills the exported rings from above |
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[f1201a] | 15 | |
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| 16 | SUB-PROCEDURES used by main procedure: |
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| 17 | get_rings,compute_ext,get_inf_def,interact1, |
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| 18 | interact2,negative_part,homog_test |
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[5480da] | 19 | "; |
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[f0c6f4] | 20 | /////////////////////////////////////////////////////////////////////////////// |
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[f1201a] | 21 | LIB "inout.lib"; |
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| 22 | LIB "general.lib"; |
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| 23 | LIB "matrix.lib"; |
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| 24 | LIB "homolog.lib"; |
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[3d124a7] | 25 | LIB "inout.lib"; |
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| 26 | LIB "general.lib"; |
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[6f2edc] | 27 | LIB "sing.lib"; |
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[3d124a7] | 28 | LIB "matrix.lib"; |
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[f1201a] | 29 | LIB "homolog.lib"; |
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[3d124a7] | 30 | /////////////////////////////////////////////////////////////////////////////// |
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[f1201a] | 31 | proc versal (ideal Fo,list #) |
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[d2b2a7] | 32 | "USAGE: versal(Fo[,d,any]); Fo=ideal, d=int, any=list |
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[f1201a] | 33 | COMUPTE: miniversal deformation of Fo up to degree d (default d=100), |
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| 34 | CREATE: Rings (exported): |
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[d2b2a7] | 35 | 'my'Px = extending the basering Po by new variables given by \"A,B,..\" |
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[f1201a] | 36 | (deformation parameters), returns as basering, |
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| 37 | the new variables come before the old ones, |
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[d2b2a7] | 38 | the ordering is the product between \"ls\" and \"ord(Po)\", |
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[f1201a] | 39 | 'my'Qx = Px/Fo extending Qo=Po/Fo, |
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| 40 | 'my'So = being the embedding-ring of the versal base space, |
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[d2b2a7] | 41 | 'my'Ox = Px/Js extending So/Js. (default my=\"\") |
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[f1201a] | 42 | Matrices (in Px, exported): |
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| 43 | Js = giving the versal base space (obstructions), |
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| 44 | Fs = giving the versal family of Fo, |
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| 45 | Rs = giving the lifting of Ro=syz(Fo). |
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| 46 | If d is defined (!=0), it computes up to degree d. |
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| 47 | If 'any' is defined and any[1] is no string, interactive version. |
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[d2b2a7] | 48 | Otherwise 'any' gives predefined strings: \"my\",\"param\",\"order\",\"out\" |
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| 49 | (\"my\" prefix-string, \"param\" is a letter (e.g. \"A\") for the name of |
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| 50 | first parameter or (e.g. \"A(\") for index parameter variables, \"order\" |
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| 51 | ordering string for ring extension), \"out\" name of output-file). |
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[f1201a] | 52 | NOTE: printlevel < 0 no output at all, |
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| 53 | printlevel >=0,1,2,.. informs you, what is going on; |
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| 54 | this proc uses 'execute'. |
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| 55 | EXAMPLE:example versal; shows an example |
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[d2b2a7] | 56 | " |
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[3d124a7] | 57 | { |
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[f1201a] | 58 | //------- prepare ------------------------------------------------------------- |
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| 59 | string str,@param,@order,@my,@out,@degrees; |
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| 60 | int @d,d_max,@t1,t1',@t2,@colR,ok_ann,@smooth,@noObstr,@size,@j; |
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| 61 | int p = printlevel-voice+3; |
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| 62 | int time = timer; |
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| 63 | intvec @iv,@jv,@is_qh,@degr; |
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| 64 | d_max = 100; |
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| 65 | @my = ""; @param="A"; @order="ds"; @out="no"; |
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| 66 | @size = size(#); |
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| 67 | if( @size>0 ) { d_max = #[1]; } |
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| 68 | if( @size>1 ) |
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| 69 | { if(typeof(#[2])!="string") |
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| 70 | { string @active; |
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| 71 | @my,@param,@order,@out = interact1(); |
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| 72 | } |
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| 73 | else |
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| 74 | { @my = #[2]; |
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| 75 | if (@size>2) {@param = #[3];} |
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| 76 | if (@size>3) {@order = #[4];} |
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| 77 | if (@size>4) {@out = #[5];} |
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| 78 | } |
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| 79 | } |
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| 80 | string myPx = @my+"Px"; |
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| 81 | string myQx = @my+"Qx"; |
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| 82 | string myOx = @my+"Ox"; |
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| 83 | string mySo = @my+"So"; |
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| 84 | Fo = simplify(Fo,10); |
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| 85 | @is_qh = qhweight(Fo); |
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| 86 | int @rowR= size(Fo); |
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| 87 | def Po = basering; |
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| 88 | setring Po; |
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| 89 | poly X_s = product(maxideal(1)); |
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| 90 | //------- reproduce T12 ------------------------------------------------------ |
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| 91 | list Ls = T12(Fo,1); |
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| 92 | matrix Ro = Ls[6]; // syz(i) |
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| 93 | matrix InfD = Ls[5]; // matrix of inf. deformations |
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| 94 | matrix PreO = Ls[7]; // representation of (Syz/Kos)* |
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| 95 | module PreO'= std(PreO); |
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| 96 | module PreT = Ls[2]; // representation of modT2 (sb) |
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| 97 | if(dim(PreT)==0) |
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| 98 | { |
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| 99 | matrix kbT2 = kbase(PreT); // kbase of T2 |
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| 100 | } |
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| 101 | else |
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| 102 | { |
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| 103 | matrix kbT2 ; // kbase of T2 : empty |
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| 104 | } |
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| 105 | @t1 = Ls[3]; // vdim of T1 |
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| 106 | @t2 = Ls[4]; // vdim of T2 |
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| 107 | kill Ls; |
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| 108 | t1' = @t1; |
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| 109 | if( @t1==0) { dbprint(p,"// rigit!"); return();} |
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| 110 | if( @t2==0) { @smooth=1; dbprint(p,"// smooth base space");} |
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| 111 | dbprint(p,"// ready: T1 and T2"); |
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| 112 | @colR = ncols(Ro); |
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| 113 | //----- test: quasi-homogeneous, choice of inf. def.-------------------------- |
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| 114 | @degrees = homog_test(@is_qh,matrix(Fo),InfD); |
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| 115 | @jv = 1..@t1; |
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| 116 | if (@degrees!="") |
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| 117 | { dbprint(p-1,"// T1 is quasi-homogeneous represented with weight-vector", |
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| 118 | @degrees); |
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| 119 | } |
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| 120 | if (defined(@active)) |
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| 121 | { "// matrix of infinitesimal deformations:";print(InfD); |
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| 122 | "// weights of infinitesimal deformations ( emty ='not qhomog'):"; |
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| 123 | @degrees; |
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| 124 | matrix dummy; |
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| 125 | InfD,dummy,t1' = interact2(InfD,@jv);kill dummy; |
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| 126 | } |
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| 127 | //---- create new rings and objects ------------------------------------------ |
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| 128 | get_rings(Fo,t1',1,@my,@order,@param); |
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| 129 | setring `myPx`; |
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| 130 | @jv=0; @jv[t1']=0; @jv=@jv+1; @jv[nvars(basering)]=0; |
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| 131 | //weight-vector for calculating |
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| 132 | //rel-jet with resp to def-para |
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| 133 | ideal Io = imap(Po,Fo); |
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| 134 | ideal J,m_J,tid; attrib(J,"isSB",1); |
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| 135 | matrix Fo = matrix(Io); //initial equations |
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| 136 | matrix homF = kohom(Fo,@colR); |
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| 137 | matrix Ro = imap(Po,Ro); |
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| 138 | matrix homR = transpose(Ro); |
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| 139 | matrix homFR= concat(homR,homF); |
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| 140 | module hom' = std(homFR); |
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| 141 | matrix Js[1][@t2]; |
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| 142 | matrix F_R,Fs,Rs,Fn,Rn; |
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| 143 | export Js,Fs,Rs; |
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| 144 | matrix Mon[t1'][1]=maxideal(1); |
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| 145 | Fn = transpose(imap(Po,InfD)*Mon); //infinitesimal deformations |
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| 146 | Fs = Fo + Fn; |
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| 147 | dbprint(p-1,"// infinitesimal deformation: Fs: ",Fs); |
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| 148 | Rn = (-1)*lift(Fo,Fs*Ro); //infinit. relations |
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| 149 | Rs = Ro + Rn; |
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| 150 | F_R = Fs*Rs; |
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| 151 | tid = 0 + ideal(F_R); |
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| 152 | if (tid[1]==0) {d_max=1;} //finished ? |
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| 153 | setring `myOx`; |
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| 154 | matrix Fs,Rs,Cup,Cup',F_R,homFR,New,Rn,Fn; |
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| 155 | module hom'; |
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| 156 | ideal null,tid; attrib(null,"isSB",1); |
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| 157 | setring `myQx`; |
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| 158 | poly X_s = imap(Po,X_s); |
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| 159 | matrix Cup,Cup',MASS; |
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| 160 | ideal tid,null; attrib(null,"isSB",1); |
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| 161 | ideal J,m_J; attrib(J,"isSB",1); |
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| 162 | attrib(m_J,"isSB",1); |
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| 163 | matrix PreO = imap(Po,PreO); |
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| 164 | module PreO'= imap(Po,PreO'); attrib(PreO',"isSB",1); |
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| 165 | module PreT = imap(Po,PreT); attrib(PreT,"isSB",1); |
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| 166 | matrix kbT2 = imap(Po,kbT2); |
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| 167 | matrix Mon = fetch(`myPx`,Mon); |
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| 168 | matrix F_R = fetch(`myPx`,F_R); |
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| 169 | matrix Js[1][@t2]; |
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[3d124a7] | 170 | //------- start the loop ------------------------------------------------------ |
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[f1201a] | 171 | for (@d=2;@d<=d_max;@d=@d+1) |
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[3d124a7] | 172 | { |
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[f1201a] | 173 | if( @t1==0) {break}; |
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| 174 | dbprint(p,"// start computation in degree "+string(@d)+"."); |
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[f0c6f4] | 175 | dbprint(p-3,">>> TIME = "+string(timer-time)); |
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| 176 | dbprint(p-3,"==> memory = "+string(kmemory())+"k"); |
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[f1201a] | 177 | //------- compute obstruction-vector ----------------------------------------- |
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| 178 | if (@smooth) { @noObstr=1;} |
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| 179 | else |
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| 180 | { Cup = jet(F_R,@d,@jv); |
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| 181 | Cup = matrix(reduce(ideal(Cup),m_J),@colR,1); |
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| 182 | Cup = jet(Cup,@d,@jv); |
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| 183 | } |
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[3d124a7] | 184 | //------- express obstructions in kbase of T2 -------------------------------- |
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[f1201a] | 185 | if ( @noObstr==0 ) |
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| 186 | { Cup' = reduce(Cup,PreO'); |
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| 187 | tid = simplify(ideal(Cup'),10); |
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| 188 | if(tid[1]!=0) |
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| 189 | { dbprint(p-4,"// *"); |
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| 190 | Cup=Cup-Cup'; |
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| 191 | } |
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| 192 | Cup = lift(PreO,Cup); |
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| 193 | MASS = lift_rel_kb(Cup,PreT,kbT2,X_s); |
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| 194 | dbprint(p-3,"// next MASSEY-products:",MASS-jet(MASS,@d-1,@jv)); |
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| 195 | if (MASS==transpose(Js)) |
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| 196 | { @noObstr=1;dbprint(p-1,"// no obstruction"); } |
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| 197 | else { @noObstr=0; } |
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[6f2edc] | 198 | } |
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[f1201a] | 199 | //------- obtain equations of base space -------------------------------------- |
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| 200 | if ( @noObstr==0 ) |
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| 201 | { Js = transpose(MASS); |
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| 202 | dbprint(p-2,"// next equation of base space:", |
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| 203 | simplify(ideal(Js),10)); |
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| 204 | setring `myPx`; |
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| 205 | Js = imap(`myQx`,Js); |
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| 206 | degBound = @d+1; |
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| 207 | J = std(ideal(Js)); |
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| 208 | m_J = std(J*ideal(Mon)); |
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| 209 | degBound = 0; |
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| 210 | //--------------- obtain new base-ring ---------------------------------------- |
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| 211 | kill `myOx`; |
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| 212 | qring `myOx` = J; |
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| 213 | matrix Fs,Rs,F_R,Cup,Cup',homFR,New,Rn,Fn; |
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| 214 | module hom'; |
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| 215 | ideal null,tid; attrib(null,"isSB",1); |
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[3d124a7] | 216 | } |
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[f1201a] | 217 | //---------------- lift equations F and relations R --------------------------- |
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| 218 | setring `myOx`; |
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| 219 | Fs = fetch(`myPx`,Fs); |
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| 220 | Rs = fetch(`myPx`,Rs); |
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| 221 | F_R = Fs*Rs; |
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| 222 | F_R = matrix(reduce(ideal(F_R),null)); |
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| 223 | tid = 0 + ideal(F_R); |
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| 224 | if (tid[1]==0) { dbprint(p-1,"// finished"); break;} |
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| 225 | Cup = (-1)*transpose(jet(F_R,@d,@jv)); |
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| 226 | homFR = fetch(`myPx`,homFR); |
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| 227 | hom' = fetch(`myPx`,hom'); attrib(hom',"isSB",1); |
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| 228 | Cup' = simplify(reduce(Cup,hom'),10); |
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| 229 | tid = simplify(ideal(Cup'),10); |
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| 230 | if (tid[1]!=0) |
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| 231 | { dbprint(p-4,"// #"); |
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| 232 | Cup=Cup-Cup'; |
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[6f2edc] | 233 | } |
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[f1201a] | 234 | New = lift(homFR,Cup); |
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| 235 | Rn = matrix(ideal(New[1+@rowR..nrows(New),1]),@rowR,@colR); |
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| 236 | Fn = matrix(ideal(New[1..@rowR,1]),1,@rowR); |
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| 237 | Fs = Fs+Fn; |
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| 238 | Rs = Rs+Rn; |
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| 239 | F_R = Fs*Rs; |
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| 240 | tid = 0+reduce(ideal(F_R),null); |
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| 241 | //---------------- fetch results into other rings ----------------------------- |
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| 242 | setring `myPx`; |
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| 243 | Fs = fetch(`myOx`,Fs); |
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| 244 | Rs = fetch(`myOx`,Rs); |
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| 245 | F_R = Fs*Rs; |
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| 246 | setring `myQx`; |
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| 247 | F_R = fetch(`myPx`,F_R); |
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| 248 | m_J = fetch(`myPx`,m_J); attrib(m_J,"isSB",1); |
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| 249 | J = fetch(`myPx`,J); attrib(J,"isSB",1); |
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| 250 | Js = fetch(`myPx`,Js); |
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| 251 | tid = fetch(`myOx`,tid); |
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| 252 | if (tid[1]==0) { dbprint(p-1,"// finished");break;} |
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[6f2edc] | 253 | } |
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[f1201a] | 254 | //--------- end loop and final output ---------------------------------------- |
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| 255 | setring `myPx`; |
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| 256 | if (@out!="no") |
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| 257 | { string out = @out+"_"+string(@d); |
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| 258 | "// writing file "+out+" with matrix Js, matrix Fs, matrix Rs ready |
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| 259 | for reading in rings "+myPx+" or "+myQx; |
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| 260 | write(out,"matrix Js[1][",@t2,"]=",Js,";matrix Fs[1][",@rowR,"]=",Fs, |
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| 261 | ";matrix Rs[",@rowR,"][",@colR,"]=",Rs,";"); |
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| 262 | } |
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[f0c6f4] | 263 | dbprint(p-3,">>> TIME = "+string(timer-time)); |
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[f1201a] | 264 | if (@is_qh != 0) |
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| 265 | { @degr = qhweight(ideal(Js)); |
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| 266 | @degr = @degr[1..t1']; |
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| 267 | dbprint(p-1,"// quasi-homogeneous weights of miniversal base",@degr); |
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| 268 | } |
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| 269 | dbprint(p-1, |
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| 270 | "// ___ Equations of miniversal base space ___",Js, |
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| 271 | "// ___ Equations of miniversal total space ___",Fs); |
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| 272 | dbprint(p,"","// Result belongs to ring "+myPx+".", |
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| 273 | "// Equations of total space of miniversal deformation are ", |
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| 274 | "// given by Fs, equations of miniversal base space by Js.", |
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| 275 | "// Make "+myPx+" the basering and list objects defined in " |
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| 276 | +myPx+" by typing:", |
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| 277 | " setring "+myPx+"; show("+myPx+");"," listvar(matrix);", |
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| 278 | "// NOTE: rings "+myQx+", "+myPx+", "+mySo+" are alive!", |
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| 279 | "// (use 'kill_rings(\""+@my+"\");' to remove)"); |
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| 280 | return(); |
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[3d124a7] | 281 | } |
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[6f2edc] | 282 | example |
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[3d124a7] | 283 | { "EXAMPLE:"; echo = 2; |
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[6f2edc] | 284 | int p = printlevel; |
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[f1201a] | 285 | printlevel = 0; |
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[6f2edc] | 286 | ring r1 = 0,(x,y,z,u,v),ds; |
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| 287 | matrix m[2][4] = x,y,z,u,y,z,u,v; |
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[f1201a] | 288 | ideal Fo = minor(m,2); |
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| 289 | // cone over rational normal curve of degree 4 |
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| 290 | versal(Fo); |
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| 291 | setring Px; |
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[6f2edc] | 292 | // ___ Equations of miniversal base space ___: |
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[f1201a] | 293 | Js;""; |
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[6f2edc] | 294 | // ___ Equations of miniversal total space ___: |
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[f1201a] | 295 | Fs;""; |
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| 296 | kill Px,Qx,So; |
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| 297 | ring r2 = 0,(x,y,z),ds; |
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| 298 | ideal Fo = x2,xy,yz,zx; |
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[6f2edc] | 299 | printlevel = 3; |
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[f1201a] | 300 | versal(Fo); |
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[6f2edc] | 301 | printlevel = p; |
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[f1201a] | 302 | kill Px,Qx,So; |
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[6f2edc] | 303 | } |
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[3d124a7] | 304 | /////////////////////////////////////////////////////////////////////////////// |
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[f1201a] | 305 | proc mod_versal(matrix Mo, ideal I, list #) |
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[d2b2a7] | 306 | " |
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[f1201a] | 307 | USAGE: mod_versal(Mo,I[,d,any]); I=ideal, M=module, d=int, any =list |
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| 308 | COMUPTE: miniversal deformation of coker(Mo) over Qo=Po/Io, Po=basering; |
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| 309 | CREATE: Ringsr (exported): |
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| 310 | 'my'Px = extending the basering by new variables |
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| 311 | (deformation parameters), |
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| 312 | the new variables come before the old ones, |
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[d2b2a7] | 313 | the ordering is the product between \"my_ord\" and \"ord(Po)\", |
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[f1201a] | 314 | 'my'Qx = Px/Io extending Qo (returns as basering), |
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| 315 | 'my'Ox = Px/(Io+Js) ring of the versal deformation of coker(Ms), |
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[d2b2a7] | 316 | 'my'So = embedding-ring of the versal base space. (default 'my'=\"\") |
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[f1201a] | 317 | Matrices (in Qx, exported): |
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| 318 | Js = giving the versal base space (obstructions), |
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| 319 | Ms = giving the versal family of Mo, |
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| 320 | Ls = giving the lifting of syzygies Lo=syz(Mo), |
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| 321 | If d is defined (!=0), it computes up to degree d. |
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| 322 | If 'any' is defined and any[1] is no string, interactive version. |
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[d2b2a7] | 323 | Otherwise 'any' gives predefined strings:\"my\",\"param\",\"order\",\"out\" |
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| 324 | (\"my\" prefix-string, \"param\" is a letter (e.g. \"A\") for the name of |
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| 325 | first parameter or (e.g. \"A(\") for index parameter variables, \"ord\" |
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| 326 | ordering string for ringextension), \"out\" name of output-file). |
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[f1201a] | 327 | NOTE: printlevel < 0 no output at all, |
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| 328 | printlevel >=0,1,2,.. informs you, what is going on, |
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| 329 | this proc uses 'execute'. |
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| 330 | EXAMPLE:example mod_versal; shows an example |
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[d2b2a7] | 331 | " |
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[3d124a7] | 332 | { |
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[f1201a] | 333 | //------- prepare ------------------------------------------------------------- |
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| 334 | string str,@param,@order,@my,@out,@degrees; |
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| 335 | int @d,d_max,f0,f1,f2,e1,e1',e2,ok_ann,@smooth,@noObstr,@size,@j; |
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| 336 | int p = printlevel-voice+3; |
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| 337 | int time = timer; |
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| 338 | intvec @iv,@jv,@is_qh,@degr; |
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| 339 | d_max = 100; |
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| 340 | @my = ""; @param="A"; @order="ds"; @out="no"; |
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| 341 | @size = size(#); |
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| 342 | if( @size>0 ) { d_max = #[1]; } |
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| 343 | if( @size>1 ) |
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| 344 | { if(typeof(#[2])!="string") |
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| 345 | { string @active; |
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| 346 | @my,@param,@order,@out = interact1(); |
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| 347 | } |
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| 348 | else |
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| 349 | { @my = #[2]; |
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| 350 | if (@size>2) {@param = #[3];} |
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| 351 | if (@size>3) {@order = #[4];} |
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| 352 | if (@size>4) {@out = #[5];} |
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| 353 | } |
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| 354 | } |
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| 355 | string myPx = @my+"Px"; |
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| 356 | string myQx = @my+"Qx"; |
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| 357 | string myOx = @my+"Ox"; |
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| 358 | string mySo = @my+"So"; |
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| 359 | @is_qh = qhweight(I); |
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| 360 | def Po = basering; |
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| 361 | setring Po; |
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| 362 | poly X_s = product(maxideal(1)); |
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| 363 | //-------- compute Ext's ------------------------------------------------------ |
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| 364 | I = std(I); |
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| 365 | qring Qo = I; |
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| 366 | matrix Mo = fetch(Po,Mo); |
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| 367 | list Lo = compute_ext(Mo,p); |
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| 368 | f0,f1,f2,e1,e2,ok_ann=Lo[1]; |
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| 369 | matrix Ls,kb1,lift1 = Lo[2],Lo[3],Lo[4]; |
---|
| 370 | matrix kb2,C',D' = Lo[5][2],Lo[5][3],Lo[5][5]; |
---|
| 371 | module ex2,Co,Do = Lo[5][1],Lo[5][4],Lo[5][6]; |
---|
| 372 | kill Lo; |
---|
| 373 | dbprint(p,"// ready: Ext1 and Ext2"); |
---|
| 374 | //----- test: quasi-homogeneous, choice of inf. def.-------------------------- |
---|
| 375 | @degrees = homog_test(@is_qh,Mo,kb1); |
---|
| 376 | e1' = e1; @jv = 1..e1; |
---|
| 377 | if (@degrees != "") |
---|
| 378 | { dbprint(p-1,"// Ext1 is quasi-homogeneous represented: "+@degrees); |
---|
| 379 | } |
---|
| 380 | if (defined(@active)) |
---|
| 381 | { "// kbase of Ext1:"; |
---|
| 382 | print(kb1); |
---|
| 383 | "// weights of kbase of Ext1 ( empty = 'not qhomog')";@degrees; |
---|
| 384 | kb1,lift1,e1' = interact2(kb1,@jv,lift1); |
---|
| 385 | } |
---|
| 386 | //-------- get new rings and objects ------------------------------------------ |
---|
| 387 | setring Po; |
---|
| 388 | get_rings(I,e1',0,@my,@order,@param); |
---|
| 389 | setring `myPx`; |
---|
| 390 | ideal J,m_J; |
---|
| 391 | ideal I_J = imap(Po,I); |
---|
| 392 | ideal Io = I_J; |
---|
| 393 | matrix Mon[e1'][1] = maxideal(1); |
---|
| 394 | matrix Ms = imap(Qo,Mo); |
---|
| 395 | matrix Ls = imap(Qo,Ls); |
---|
| 396 | matrix Js[1][e2]; |
---|
| 397 | setring `myQx`; |
---|
| 398 | ideal J,I_J,tet,null; attrib(null,"isSB",1); |
---|
| 399 | ideal m_J = fetch(`myPx`,m_J); attrib(m_J,"isSB",1); |
---|
| 400 | @jv=0; @jv[e1] = 0; @jv = @jv+1; @jv[nvars(`myPx`)] = 0; |
---|
| 401 | matrix Ms = imap(Qo,Mo); export(Ms); |
---|
| 402 | matrix Ls = imap(Qo,Ls); export(Ls); |
---|
| 403 | matrix Js[e2][1]; export(Js); |
---|
| 404 | matrix MASS; |
---|
| 405 | matrix Mon = fetch(`myPx`,Mon); |
---|
| 406 | matrix Mn,Ln,ML,Cup,Cup',Lift; |
---|
| 407 | matrix C' = imap(Qo,C'); |
---|
| 408 | module Co = imap(Qo,Co); attrib(Co,"isSB",1); |
---|
| 409 | module ex2 = imap(Qo,ex2); attrib(ex2,"isSB",1); |
---|
| 410 | matrix D' = imap(Qo,D'); |
---|
| 411 | module Do = imap(Qo,Do); attrib(Do,"isSB",1); |
---|
| 412 | matrix kb2 = imap(Qo,kb2); |
---|
| 413 | matrix kb1 = imap(Qo,kb1); |
---|
| 414 | matrix lift1= imap(Qo,lift1); |
---|
| 415 | poly X_s = imap(Po,X_s); |
---|
| 416 | intvec intv = e1',e1,f0,f1,f2; |
---|
| 417 | Ms,Ls= get_inf_def(Ms,Ls,kb1,lift1,X_s); |
---|
| 418 | kill kb1,lift1; |
---|
| 419 | dbprint(p-1,"// infinitesimal extension",Ms); |
---|
| 420 | //----------- start the loop -------------------------------------------------- |
---|
| 421 | for (@d=2;@d<=d_max;@d=@d+1) |
---|
| 422 | { |
---|
[f0c6f4] | 423 | dbprint(p-3,">>> time = "+string(timer-time)); |
---|
| 424 | dbprint(p-3,"==> memory = "+string(memory(0)/1000)+ |
---|
[f1201a] | 425 | ", allocated = "+string(memory(1)/1000)); |
---|
| 426 | dbprint(p,"// start deg = "+string(@d)); |
---|
| 427 | //-------- get obstruction ---------------------------------------------------- |
---|
| 428 | Cup = matrix(ideal(Ms*Ls),f0*f2,1); |
---|
| 429 | Cup = jet(Cup,@d,@jv); |
---|
| 430 | Cup = reduce(ideal(Cup),m_J); |
---|
| 431 | Cup = jet(Cup,@d,@jv); |
---|
| 432 | //-------- express obstruction in kbase --------------------------------------- |
---|
| 433 | Cup' = reduce(Cup,Do); |
---|
| 434 | tet = simplify(ideal(Cup'),10); |
---|
| 435 | if (tet[1]!=0) |
---|
| 436 | { dbprint(p-4,"// *"); |
---|
| 437 | Cup = Cup-Cup'; |
---|
| 438 | } |
---|
| 439 | Cup = lift(D',Cup); |
---|
| 440 | if (ok_ann) |
---|
| 441 | { MASS = lift_rel_kb(Cup,ex2,kb2,X_s);} |
---|
| 442 | else |
---|
| 443 | { MASS = reduce(Cup,ex2);} |
---|
| 444 | dbprint(p-3,"// next MATRIC-MASSEY-products", |
---|
| 445 | MASS-jet(MASS,@d-1,@jv)); |
---|
| 446 | if ( MASS==transpose(Js)) |
---|
| 447 | { @noObstr = 1;dbprint(p-1,"//no obstruction"); } |
---|
| 448 | else { @noObstr = 0; } |
---|
| 449 | //-------- obtain equations of base space ------------------------------------- |
---|
| 450 | if (@noObstr == 0) |
---|
| 451 | { Js = MASS; |
---|
| 452 | dbprint(p-2,"// next equation of base space:",simplify(ideal(Js),10)); |
---|
| 453 | setring `myPx`; |
---|
| 454 | Js = imap(`myQx`,Js); |
---|
| 455 | degBound=@d+1; |
---|
| 456 | J = std(ideal(Js)); |
---|
| 457 | m_J = std(ideal(Mon)*J); |
---|
| 458 | degBound=0; |
---|
| 459 | I_J = Io,J; attrib(I_J,"isSB",1); |
---|
| 460 | //-------- obtain new base ring ----------------------------------------------- |
---|
| 461 | kill `myOx`; |
---|
| 462 | qring `myOx` = I_J; |
---|
| 463 | ideal null,tet; attrib(null,"isSB",1); |
---|
| 464 | matrix Ms = imap(`myQx`,Ms); |
---|
| 465 | matrix Ls = imap(`myQx`,Ls); |
---|
| 466 | matrix Mn,Ln,ML,Cup,Cup',Lift; |
---|
| 467 | matrix C' = imap(Qo,C'); |
---|
| 468 | module Co = imap(Qo,Co); attrib(Co,"isSB",1); |
---|
| 469 | module ex2 = imap(Qo,ex2); attrib(ex2,"isSB",1); |
---|
| 470 | matrix kb2 = imap(Qo,kb2); |
---|
| 471 | poly X_s = imap(Po,X_s); |
---|
| 472 | } |
---|
| 473 | //-------- get lifts ---------------------------------------------------------- |
---|
| 474 | setring `myOx`; |
---|
| 475 | ML = matrix(reduce(ideal(Ms*Ls),null),f0,f2); |
---|
| 476 | Cup = matrix(ideal(ML),f0*f2,1); |
---|
| 477 | Cup = jet(Cup,@d,@jv); |
---|
| 478 | Cup'= reduce(Cup,Co); |
---|
| 479 | tet = simplify(ideal(Cup'),10); |
---|
| 480 | if (tet[1]!=0) |
---|
| 481 | { dbprint(p-4,"// #"); |
---|
| 482 | Cup = Cup-Cup'; |
---|
| 483 | } |
---|
| 484 | Lift = lift(C',Cup); |
---|
| 485 | Mn = matrix(ideal(Lift),f0,f1); |
---|
| 486 | Ln = matrix(ideal(Lift[f0*f1+1..nrows(Lift),1]),f1,f2); |
---|
| 487 | Ms = Ms-Mn; |
---|
| 488 | Ls = Ls-Ln; |
---|
| 489 | dbprint(p-3,"// next extension of Mo",Mn); |
---|
| 490 | dbprint(p-3,"// next extension of syz(Mo)",Ln); |
---|
| 491 | ML = reduce(ideal(Ms*Ls),null); |
---|
| 492 | //--------- test: finished ---------------------------------------------------- |
---|
| 493 | tet = simplify(ideal(ML),10); |
---|
| 494 | if (tet[1]==0) { dbprint(p-1,"// finished in degree ",@d);} |
---|
| 495 | //---------fetch results into Qx and Px --------------------------------------- |
---|
| 496 | setring `myPx`; |
---|
| 497 | Ms = fetch(`myOx`,Ms); |
---|
| 498 | Ls = fetch(`myOx`,Ls); |
---|
| 499 | setring `myQx`; |
---|
| 500 | Ms = fetch(`myOx`,Ms); |
---|
| 501 | Ls = fetch(`myOx`,Ls); |
---|
| 502 | ML = Ms*Ls; |
---|
| 503 | ML = matrix(reduce(ideal(ML),null),f0,f2); |
---|
| 504 | tet = imap(`myOx`,tet); |
---|
| 505 | if (tet[1]==0) { break;} |
---|
| 506 | } |
---|
| 507 | //------- end of loop, final output ------------------------------------------- |
---|
| 508 | if (@out != "no") |
---|
| 509 | { string out = @out+"_"+string(@d); |
---|
| 510 | "// writing file '"+out+"' with matrix Js, matrix Ms, matrix Ls |
---|
| 511 | ready for reading in rings "+myPx+" or "+myQx; |
---|
| 512 | write(out,"matrix Js[1][",e2,"]=",Js,";matrix Ms[",f0,"][",f1,"]=",Ms, |
---|
| 513 | ";matrix Ls[",f1,"][",f2,"]=",Ls,";"); |
---|
| 514 | } |
---|
[f0c6f4] | 515 | dbprint(p-3,">>> TIME = "+string(timer-time)); |
---|
[f1201a] | 516 | if (@is_qh != 0) |
---|
| 517 | { @degr = qhweight(ideal(Js)); |
---|
| 518 | @degr = @degr[1..e1']; |
---|
| 519 | dbprint(p-1,"// quasi-homogeneous weights of miniversal base",@degr); |
---|
| 520 | } |
---|
| 521 | dbprint(p-1,"// Result belongs to qring "+myQx, |
---|
| 522 | "// Equations of total space of miniversal deformation are in Js", |
---|
| 523 | simplify(ideal(Js),10), |
---|
| 524 | "// Matrix of the deformed module is Ms and lifted syzygies are Ls.", |
---|
| 525 | "// Make "+myQx+" the basering and list objects defined in "+myQx+ |
---|
| 526 | " by typing:", |
---|
| 527 | " listvar(ring);setring "+myQx+"; show("+myQx+");listvar(ideal);"+ |
---|
| 528 | "listvar(matrix);", |
---|
| 529 | "// NOTE: rings "+myQx+", "+myOx+", "+mySo+" are still alive!", |
---|
| 530 | "// (use: 'kill_rings("+@my+");' to remove them)"); |
---|
| 531 | return(); |
---|
[3d124a7] | 532 | } |
---|
[6f2edc] | 533 | example |
---|
[3d124a7] | 534 | { "EXAMPLE:"; echo = 2; |
---|
[f1201a] | 535 | int p = printlevel; |
---|
| 536 | printlevel = 1; |
---|
| 537 | ring Ro = 0,(x,y),wp(3,4); |
---|
| 538 | ideal Io = x4+y3; |
---|
| 539 | matrix Mo[2][2] = x2,y,-y2,x2; |
---|
| 540 | mod_versal(Mo,Io); |
---|
| 541 | printlevel = p; |
---|
| 542 | kill Px,Qx,So; |
---|
[3d124a7] | 543 | } |
---|
[f1201a] | 544 | //============================================================================= |
---|
[3d124a7] | 545 | /////////////////////////////////////////////////////////////////////////////// |
---|
[f1201a] | 546 | proc kill_rings(list #) |
---|
[d2b2a7] | 547 | "USAGE: kill_rings([string]); |
---|
[f1201a] | 548 | Sub-procedure: kills exported rings of 'versal' and |
---|
| 549 | 'mod_versal' with prefix 'string' |
---|
[d2b2a7] | 550 | " |
---|
[3d124a7] | 551 | { |
---|
[f1201a] | 552 | string my,br; |
---|
| 553 | if (size(#)>0) { my = #[1];} |
---|
| 554 | string na=nameof(basering); |
---|
| 555 | br = my+"Qx"; |
---|
| 556 | if (defined(`br`)) { kill `br`;} |
---|
| 557 | br = my+"Px"; |
---|
| 558 | if (defined(`br`)) { kill `br`;} |
---|
| 559 | br = my+"So"; |
---|
| 560 | if (defined(`br`)) { kill `br`;} |
---|
| 561 | br = my+"Ox"; |
---|
| 562 | if (defined(`br`)) { kill `br`;} |
---|
| 563 | br = my+"Sx"; |
---|
| 564 | if (defined(`br`)) { kill `br`} |
---|
| 565 | if (defined(basering)==0) |
---|
| 566 | { "// choose new basering?"; |
---|
| 567 | listvar(ring); |
---|
| 568 | } |
---|
| 569 | return(); |
---|
[3d124a7] | 570 | } |
---|
| 571 | /////////////////////////////////////////////////////////////////////////////// |
---|
[f1201a] | 572 | proc compute_ext(matrix Mo,int p) |
---|
[d2b2a7] | 573 | " |
---|
[f1201a] | 574 | Sub-procedure: obtain Ext1 and Ext2 and other objects used by mod_versal |
---|
[d2b2a7] | 575 | " |
---|
[f1201a] | 576 | { |
---|
| 577 | int l,f0,f1,f2,f3,e1,e2,ok_ann; |
---|
| 578 | module Co,Do,ima,ex1,ex2; |
---|
| 579 | matrix M0,M1,M2,ker,kb1,lift1,kb2,A,B,C,D; |
---|
| 580 | //------- resM --------------------------------------------------------------- |
---|
| 581 | list resM = res(Mo,3); |
---|
| 582 | M0 = resM[1]; |
---|
| 583 | M1 = resM[2]; |
---|
| 584 | M2 = resM[3]; kill resM; |
---|
| 585 | f0 = nrows(M0); |
---|
| 586 | f1 = ncols(M0); |
---|
| 587 | f2 = ncols(M1); |
---|
| 588 | f3 = ncols(M2); |
---|
| 589 | //------ compute Ext^2 ------------------------------------------------------ |
---|
| 590 | B = kohom(M0,f3); |
---|
| 591 | A = kontrahom(M2,f0); |
---|
| 592 | D = modulo(A,B); |
---|
| 593 | Do = std(D); |
---|
| 594 | ima = kohom(M0,f2),kontrahom(M1,f0); |
---|
| 595 | ex2 = modulo(D,ima); |
---|
| 596 | ex2 = std(ex2); |
---|
| 597 | e2 = vdim(ex2); |
---|
| 598 | kb2 = kbase(ex2); |
---|
| 599 | dbprint(p,"// vdim (Ext^2) = "+string(e2)); |
---|
| 600 | //------ test: max = Ann(Ext2) ----------------------------------------------- |
---|
| 601 | for (l=1;l<=e2;l=l+1) |
---|
| 602 | { ok_ann = ok_ann+ord(kb2[l]); |
---|
| 603 | } |
---|
| 604 | if (ok_ann==0) |
---|
| 605 | { e2 =nrows(ex2); |
---|
| 606 | dbprint(p,"// Ann(Ext2) is maximal"); |
---|
| 607 | } |
---|
| 608 | //------ compute Ext^1 ------------------------------------------------------- |
---|
| 609 | B = kohom(M0,f2); |
---|
| 610 | A = kontrahom(M1,f0); |
---|
| 611 | ker = modulo(A,B); |
---|
| 612 | ima = kohom(M0,f1),kontrahom(M0,f0); |
---|
| 613 | ex1 = modulo(ker,ima); |
---|
| 614 | ex1 = std(ex1); |
---|
| 615 | e1 = vdim(ex1); |
---|
| 616 | dbprint(p,"// vdim (Ext^1) = "+string(e1)); |
---|
| 617 | kb1 = kbase(ex1); |
---|
| 618 | kb1 = ker*kb1; |
---|
| 619 | C = concat(A,B); |
---|
| 620 | Co = std(C); |
---|
| 621 | //------ compute the liftings of Ext^1 --------------------------------------- |
---|
| 622 | lift1 = A*kb1; |
---|
| 623 | lift1 = lift(B,lift1); |
---|
| 624 | intvec iv = f0,f1,f2,e1,e2,ok_ann; |
---|
| 625 | list L' = ex2,kb2,C,Co,D,Do; |
---|
| 626 | return(iv,M1,kb1,lift1,L'); |
---|
[3d124a7] | 627 | } |
---|
[f1201a] | 628 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 629 | proc get_rings(ideal Io,int e1,int switch, list #) |
---|
[d2b2a7] | 630 | " |
---|
[f1201a] | 631 | Sub-procedure: creating ring-extensions |
---|
[d2b2a7] | 632 | " |
---|
[f1201a] | 633 | { |
---|
| 634 | def Po = basering; |
---|
| 635 | string my; |
---|
| 636 | string my_ord = "ds"; |
---|
| 637 | string my_var = "A"; |
---|
| 638 | if (size(#)>2) |
---|
[3d124a7] | 639 | { |
---|
[f1201a] | 640 | my = #[1]; |
---|
| 641 | my_ord = #[2]; |
---|
| 642 | my_var = #[3]; |
---|
[3d124a7] | 643 | } |
---|
[f1201a] | 644 | string my_Px = my+"Px"; |
---|
| 645 | string my_Qx = my+"Qx"; |
---|
| 646 | string my_Ox = my+"Ox"; |
---|
| 647 | string my_So = my+"So"; |
---|
| 648 | extendring(my_Px,e1,my_var,my_ord); |
---|
| 649 | ideal Io = imap(Po,Io); attrib(Io,"isSB",1); |
---|
| 650 | my ="qring "+my_Qx+" = Io; export("+my_Qx+");"; |
---|
| 651 | execute(my); |
---|
| 652 | if (switch) |
---|
[3d124a7] | 653 | { |
---|
[f1201a] | 654 | setring `my_Px`; |
---|
| 655 | my = "qring "+my_Ox+" = std(ideal(0));export("+my_Ox+");"; |
---|
[3d124a7] | 656 | } |
---|
[f1201a] | 657 | else |
---|
[6f2edc] | 658 | { |
---|
[f1201a] | 659 | my = "def "+my_Ox+" = "+my_Qx+";export("+my_Ox+");"; |
---|
[3d124a7] | 660 | } |
---|
[f1201a] | 661 | execute(my); |
---|
| 662 | defring(my_So,charstr(Po),e1,my_var,my_ord); |
---|
| 663 | return(); |
---|
[3d124a7] | 664 | } |
---|
[f1201a] | 665 | ////////////////////////////////////////////////////////////////////////////// |
---|
[d2b2a7] | 666 | proc get_inf_def(list #) |
---|
| 667 | " |
---|
[f1201a] | 668 | Sub-procedure: compute infinitesimal family of a module and its syzygies |
---|
| 669 | from a kbase of Ext1 and its lifts |
---|
[d2b2a7] | 670 | " |
---|
[f1201a] | 671 | { |
---|
| 672 | matrix Ms = #[1]; |
---|
| 673 | matrix Ls = #[2]; |
---|
| 674 | matrix kb1 = #[3]; |
---|
| 675 | matrix li1 = #[4]; |
---|
| 676 | int e1,f0,f1,f2; |
---|
| 677 | poly X_s = #[5]; |
---|
| 678 | e1 = ncols(kb1); |
---|
| 679 | f0 = nrows(Ms); |
---|
| 680 | f1 = nrows(Ls); |
---|
| 681 | f2 = ncols(Ls); |
---|
| 682 | int l; |
---|
| 683 | for (l=1;l<=e1;l=l+1) |
---|
| 684 | { |
---|
| 685 | Ms = Ms + var(l)*matrix(ideal(kb1[l]),f0,f1); |
---|
| 686 | Ls = Ls - var(l)*matrix(ideal(li1[l]),f1,f2); |
---|
| 687 | } |
---|
| 688 | return(Ms,Ls); |
---|
| 689 | } |
---|
| 690 | ////////////////////////////////////////////////////////////////////////////// |
---|
| 691 | proc lift_rel_kb (module N, module M, list #) |
---|
[d2b2a7] | 692 | " |
---|
[f1201a] | 693 | USAGE lift_rel_kb(N,M[,kbaseM,p]); |
---|
| 694 | ASSUME [p a monomial ] or the product of all variables |
---|
| 695 | N, M modules of same rank, |
---|
| 696 | M depending only on variables not in p and vdim(M) finite in this ring, |
---|
| 697 | [ kbaseM the kbase of M in the subring given by variables not in p ] |
---|
| 698 | warning: check that these assumtions are fulfilled! |
---|
| 699 | RETURN matrix A, whose j-th columnes present the coeff's of N[j] in kbaseM, |
---|
| 700 | i.e. kbaseM*A = reduce(N,std(M)) |
---|
| 701 | EXAMPLE example lift_rel_kb; shows examples |
---|
[d2b2a7] | 702 | " |
---|
[f1201a] | 703 | { |
---|
| 704 | poly p = product(maxideal(1)); |
---|
| 705 | M = std(M); |
---|
| 706 | matrix A; |
---|
| 707 | if (size(#)>0) { p=#[2]; module kbaseM=#[1];} |
---|
| 708 | else |
---|
| 709 | { if (vdim(M)<=0) { "// vdim(M) not finite";return(A);} |
---|
| 710 | module kbaseM = kbase(M); |
---|
| 711 | } |
---|
| 712 | N = reduce(N,M); |
---|
| 713 | if (simplify(N,10)[1]==[0]) {return(A);} |
---|
| 714 | A = coeffs(N,kbaseM,p); |
---|
| 715 | return(A); |
---|
| 716 | } |
---|
[3d124a7] | 717 | example |
---|
[f1201a] | 718 | { |
---|
| 719 | "EXAMPLE"; echo=2; |
---|
| 720 | ring r=0,(A,B,x,y),dp; |
---|
| 721 | module M = [x2,xy],[xy,y3],[y2],[0,x]; |
---|
| 722 | module kbaseM = [1],[x],[xy],[y],[0,1],[0,y],[0,y2]; |
---|
| 723 | poly f=xy; |
---|
| 724 | module N = [AB,BBy],[A3xy+x4,AB*(1+y2)]; |
---|
| 725 | matrix A = lift_rel_kb(N,M,kbaseM,f); |
---|
| 726 | print(A); |
---|
| 727 | "TEST:"; |
---|
| 728 | print(matrix(kbaseM)*A-matrix(reduce(N,std(M)))); |
---|
| 729 | "2nd EXAMPLE"; |
---|
| 730 | ring r = 100,(x,y),dp; |
---|
| 731 | ideal I = x2+y2,x2y; |
---|
| 732 | module M = jacob(I)+I*freemodule(2); |
---|
| 733 | module N = [x+y,1+x2+xy]; |
---|
| 734 | matrix A = lift_rel_kb(N,M); |
---|
[3d124a7] | 735 | print(A); |
---|
[f1201a] | 736 | print(kbase(std(M))*A); |
---|
| 737 | print(reduce(N,std(M))); |
---|
| 738 | } |
---|
[f0c6f4] | 739 | /////////////////////////////////////////////////////////////////////////////// |
---|
| 740 | proc lift_kbase (N, M) |
---|
[d2b2a7] | 741 | "USAGE: lift_kbase(N,M); N,M=poly/ideal/vector/module |
---|
[f0c6f4] | 742 | RETURN: matrix A, coefficient matrix expressing N as linear combination of |
---|
| 743 | k-basis of M. Let the k-basis have k elements and size(N)=c columns. |
---|
| 744 | Then A satisfies: |
---|
| 745 | matrix(reduce(N,std(M)),k,c) = matrix(kbase(std(M)))*A |
---|
| 746 | ASSUME: dim(M)=0 and the monomial ordering is a well ordering or the last |
---|
| 747 | block of the ordering is c or C |
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| 748 | EXAMPLE: example lift_kbase; shows an example |
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[d2b2a7] | 749 | " |
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[f0c6f4] | 750 | { |
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| 751 | return(lift_rel_kb(N,M)); |
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| 752 | } |
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| 753 | example |
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| 754 | {"EXAMPLE:"; echo=2; |
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| 755 | ring R=0,(x,y),ds; |
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| 756 | module M=[x2,xy],[y2,xy],[0,xx],[0,yy]; |
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| 757 | module N=[x3+xy,x],[x,x+y2]; |
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| 758 | print(M); |
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| 759 | module kb=kbase(std(M)); |
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| 760 | print(kb); |
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| 761 | print(N); |
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| 762 | matrix A=lift_kbase(N,M); |
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| 763 | print(A); |
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| 764 | matrix(reduce(N,std(M)),nrows(kb),ncols(A)) - matrix(kbase(std(M)))*A; |
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| 765 | } |
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| 766 | |
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| 767 | |
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[f1201a] | 768 | /////////////////////////////////////////////////////////////////////////////// |
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| 769 | proc interact1 () |
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[d2b2a7] | 770 | " |
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[f1201a] | 771 | Sub_procedure: asking for and reading your input-strings |
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[d2b2a7] | 772 | " |
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[f1201a] | 773 | { |
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| 774 | string my = "@"; |
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| 775 | string str,out,my_ord,my_var; |
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| 776 | my_ord = "ds"; |
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| 777 | my_var = "A"; |
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| 778 | "INPUT: name of output-file (ENTER = no output, do not use \"my\"!)"; |
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| 779 | str = read(""); |
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| 780 | if (size(str)>1) |
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| 781 | { out = str[1..size(str)-1];} |
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| 782 | else |
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| 783 | { out = "no";} |
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| 784 | "INPUT: prefix-string of ring-extension (ENTER = '@')"; |
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| 785 | str = read(""); |
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| 786 | if ( size(str) > 1 ) |
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| 787 | { my = str[1..size(str)-1]; } |
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| 788 | "INPUT:parameter-string |
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| 789 | (give a letter corresponding to first new variable followed by the next letters, |
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| 790 | or 'T(' - a letter + '(' - getting a string of indexed variables) |
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| 791 | (ENTER = A) :"; |
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| 792 | str = read(""); |
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| 793 | if (size(str)>1) { my_var=str[1..size(str)-1]; } |
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| 794 | "INPUT:order-string (local or weighted!) (ENTER = ds) :"; |
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| 795 | str = read(""); |
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| 796 | if (size(str)>1) { my_ord=str[1..size(str)-1]; } |
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| 797 | if( find(my_ord,"s")+find(my_ord,"w") == 0 ) |
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| 798 | { "// ordering must be an local! changed into 'ds'"; |
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| 799 | my_ord = "ds"; |
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| 800 | } |
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| 801 | return(my,my_var,my_ord,out); |
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[3d124a7] | 802 | } |
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| 803 | /////////////////////////////////////////////////////////////////////////////// |
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[f1201a] | 804 | proc interact2 (matrix A, intvec col_vec, list #) |
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[d2b2a7] | 805 | " |
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[f1201a] | 806 | Sub-procedure: asking for and reading your input |
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[d2b2a7] | 807 | " |
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[3d124a7] | 808 | { |
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[f1201a] | 809 | module B,C; |
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| 810 | matrix D; |
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| 811 | int flag; |
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| 812 | if (size(#)>0) { D=#[1];flag=1;} |
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| 813 | int t1 = ncols(A); |
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| 814 | ">>Do you want all deformations? (ENTER=yes)"; |
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| 815 | string str = read(""); |
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| 816 | if (size(str)>1) |
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| 817 | { ">> Choose columnes of the matrix"; |
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| 818 | ">> (Enter = all columnes)"; |
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| 819 | "INPUT (number of columnes to use as integer-list 'i_1,i_2,.. ,i_t' ):"; |
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| 820 | string columnes = read(""); |
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| 821 | if (size(columnes)<2) {columnes=string(col_vec);} |
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| 822 | t1 = size(columnes)/2; |
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| 823 | int l,l1; |
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| 824 | for (l=1;l<=t1;l=l+1) |
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[3d124a7] | 825 | { |
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[f1201a] | 826 | execute("l1= "+columnes[2*l-1]+";"); |
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| 827 | B[l] = A[l1]; |
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| 828 | if(flag) { C[l]=D[l1];} |
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[3d124a7] | 829 | } |
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[f1201a] | 830 | A = matrix(B,nrows(A),size(B)); |
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| 831 | D = matrix(C,nrows(D),size(C)); |
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[6f2edc] | 832 | } |
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[f1201a] | 833 | return(A,D,t1); |
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[6f2edc] | 834 | } |
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[f1201a] | 835 | /////////////////////////////////////////////////////////////////////////////// |
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| 836 | proc negative_part(intvec iv) |
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[d2b2a7] | 837 | " |
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[f1201a] | 838 | RETURNS intvec of indices of jv having negative entries (or iv, if non) |
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[d2b2a7] | 839 | " |
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[f1201a] | 840 | { |
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| 841 | intvec jv; |
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| 842 | int l,k; |
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| 843 | for (l=1;l<=size(iv);l=l+1) |
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| 844 | { if (iv[l]<0) |
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| 845 | { k = k+1; |
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| 846 | jv[k]=l; |
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| 847 | } |
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| 848 | } |
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[75089b] | 849 | if (jv==0) {jv=1; dbprint(printlevel-1,"// empty negative part, return all ");} |
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[f1201a] | 850 | return(jv); |
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[3d124a7] | 851 | } |
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| 852 | /////////////////////////////////////////////////////////////////////////////// |
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[f1201a] | 853 | proc find_ord(matrix A, intvec w_vec) |
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[d2b2a7] | 854 | " |
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[f1201a] | 855 | Sub-proc: return martix ord(a_ij) with respect to weight_vec, or |
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| 856 | 0 if A non-qh |
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[d2b2a7] | 857 | " |
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[f1201a] | 858 | { |
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| 859 | int @r = nrows(A); |
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| 860 | int @c = ncols(A); |
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| 861 | int i,j; |
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| 862 | string ord_str = "wp("+string(w_vec)+")"; |
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| 863 | def br = basering; |
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| 864 | changeord("nr",ord_str); |
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| 865 | matrix A = imap(br,A); |
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| 866 | intmat degA[@r][@c]; |
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| 867 | if (homog(ideal(A))) |
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| 868 | { for (i=1;i<=@r;i=i+1) |
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| 869 | { for(j=1;j<=@c;j=j+1) |
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| 870 | { degA[i,j]=ord(A[i,j]); } |
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| 871 | } |
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| 872 | } |
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| 873 | setring br; |
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| 874 | kill nr; |
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| 875 | return(degA); |
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| 876 | } |
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| 877 | ////////////////////////////////////////////////////////////////////////////////// |
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| 878 | proc homog_test(intvec w_vec, matrix Mo, matrix A) |
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[d2b2a7] | 879 | " |
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[f1201a] | 880 | Sub proc: return relative weight string of columnes of A with respect |
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[d2b2a7] | 881 | to the given w_vec and to Mo, or \"\" if not qh |
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[f1201a] | 882 | NOTE: * means weight is not determined |
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[d2b2a7] | 883 | " |
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[f1201a] | 884 | { |
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| 885 | int k,l; |
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| 886 | intvec tv; |
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| 887 | string @nv; |
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| 888 | int @r = nrows(A); |
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| 889 | int @c = ncols(A); |
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| 890 | A = concat(matrix(ideal(Mo),@r,1),A); |
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| 891 | intmat a = find_ord(A,w_vec); |
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| 892 | intmat b[@r][@c]; |
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| 893 | for (l=1;l<=@c;l=l+1) |
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| 894 | { |
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| 895 | for (k=1;k<=@r;k=k+1) |
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| 896 | { if (A[k,l+1]!=0) |
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| 897 | { b[k,l] = a[k,l+1]-a[k,1];} |
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| 898 | } |
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| 899 | tv = 0; |
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| 900 | for (k=1;k<=@r;k=k+1) |
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| 901 | { if (A[k,l+1]*A[k,1]!=0) |
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| 902 | {tv = tv,b[k,l];} |
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| 903 | } |
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| 904 | if (size(tv)>1) |
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| 905 | { k = tv[2]; |
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| 906 | tv = tv[2..size(tv)]; tv = tv -k; |
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| 907 | if (tv==0) { @nv = @nv+string(-k)+",";} |
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| 908 | else {return("");} |
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| 909 | } |
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| 910 | else { @nv = @nv+"*,";} |
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| 911 | } |
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| 912 | @nv = @nv[1..size(@nv)-1]; |
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| 913 | return(@nv); |
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| 914 | } |
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| 915 | ////////////////////////////////////////////////////////////////////////////////// |
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| 916 | proc homog_t(intvec d_vec, matrix Fo, matrix A) |
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[d2b2a7] | 917 | " |
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[f1201a] | 918 | Sub-procedure: Computing relative (with respect to flatten(Fo)) weight_vec |
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| 919 | of columnes of A (return zero if Fo or A not qh) |
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[d2b2a7] | 920 | " |
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[f1201a] | 921 | { |
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| 922 | Fo = matrix(Fo,nrows(A),1); |
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| 923 | A = concat(Fo,A); |
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| 924 | A = transpose(A); |
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| 925 | def br = basering; |
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| 926 | string o_str = "wp("+string(d_vec)+")"; |
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| 927 | changeord("nr",o_str); |
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| 928 | module A = fetch(br,A); |
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| 929 | intvec dv; |
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| 930 | int l = homog(A) ; |
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| 931 | if (l==0) {setring br; kill nr; return(l);} |
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| 932 | dv = attrib(A,"isHomog"); |
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| 933 | l = dv[1]; |
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| 934 | dv = dv[2..size(dv)]; |
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| 935 | dv = dv-l; |
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| 936 | setring br; |
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| 937 | kill nr; |
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| 938 | return(dv); |
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| 939 | } |
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