Changeset 8b87364 in git for Singular/LIB/standard.lib

Timestamp:

Nov 5, 2001, 5:06:29 PM (22 years ago)

Author:

Gerhard Pfister <pfister@…>

Branches:

(u'spielwiese', '8e0ad00ce244dfd0756200662572aef8402f13d5')

Children:

16105c8f405ac4e9d787fbd2bae347a9686645db

Parents:

5b3302cc6f7c9964ee19073aca0b273ad9e606a9

Message:

neue proceduren eingefuegt


git-svn-id: file:///usr/local/Singular/svn/trunk@5668 2c84dea3-7e68-4137-9b89-c4e89433aadc

File:

• Singular/LIB/standard.lib (modified) (3 diffs)

Singular/LIB/standard.lib

@@ -1 +1 @@
 //////////////////////////////////////////////////////////////////////////////
-version="$Id: standard.lib,v 1.60 2001-08-28 12:54:05 Singular Exp $";
+version="$Id: standard.lib,v 1.61 2001-11-05 16:05:08 pfister Exp $";
 category="Miscellaneous";
 info="
@@ -14 +14 @@
  fprintf(link,fmt,..)   writes formatted string to link
  printf(fmt,...)        displays formatted string
+ timeStd(i,d)           std(i) if the standard basis computation finished after
+                        d-1 seconds and i otherwhise
+ timeFactorize(p,d)     factorize(p) if the factorization finished after d-1 
+                        seconds otherwhise f is considered to be irreducible
+factorH(p)              changes variables to become the last variable the 
+                        principal one in the multivariate factorization and 
+                        factorizes then the polynomial
+
 ";
 
@@ -1025 +1033 @@
 }
 
+proc timeFactorize(poly i,list #)
+"USAGE:  timeFactorize(p,d)  poly p , integer d
+RETURN:  factorize(p) if the factorization finished after d-1 
+         seconds otherwhise f is considered to be irreducible
+EXAMPLE: example timeFactorize; shows an example
+"
+{
+  def P=basering;
+  if (size(#) > 0)
+  {
+    if (system("with", "MP"))
+    {
+      if ((typeof(#[1]) == "int")&&(#[1]))
+      {
+        int wait = #[1];
+        int j = 10;
+
+        string bs = nameof(basering);
+        link l_fork = "MPtcp:fork";
+        open(l_fork);
+        write(l_fork, quote(system("pid")));
+        int pid = read(l_fork);
+        write(l_fork, quote(timeFactorize(eval(i))));
+
+        // sleep in small intervalls for appr. one second
+        if (wait > 0)
+        {
+          while(j < 1000000)
+          {
+            if (status(l_fork, "read", "ready", j)) {break;}
+            j = j + j;
+          }
+        }
+
+        // sleep in intervalls of one second from now on
+        j = 1;
+        while (j < wait)
+        {
+          if (status(l_fork, "read", "ready", 1000000)) {break;}
+          j = j + 1;
+        }
+
+        if (status(l_fork, "read", "ready"))
+        {
+          def result = read(l_fork);
+          if (bs != nameof(basering))
+          {
+            def PP = basering;
+            setring P;
+            def result = imap(PP, result);
+            kill PP;
+          }
+          kill (l_fork);
+        }
+        else
+        {
+          list result;
+          intvec v=1,1;
+          result[1]=list(1,i);
+          result[2]=v;
+          j = system("sh", "kill " + string(pid));
+        }
+        return (result);
+      }
+    }
+  }
+  return(factorH(i));
+}
+example
+{ "EXAMPLE:"; echo = 2;
+   ring r=0,(x,y),dp;
+   poly p=((x2+y3)^2+xy6)*((x3+y2)^2+x10y);
+   p=p^2;
+   timeFactorize(p,2);
+   timeFactorize(p,20);
+}
+
+proc timeStd(ideal i,list #)
+"USAGE:  timeStd(i,d), i ideal, d integer
+RETURN:  std(i) if the standard basis computation finished after
+         d-1 seconds and i otherwhise
+EXAMPLE: example timeStd; shows an example
+"
+{
+  def P=basering;
+  if (size(#) > 0)
+  {
+    if (system("with", "MP"))
+    {
+      if ((typeof(#[1]) == "int")&&(#[1]))
+      {
+        int wait = #[1];
+        int j = 10;
+
+        string bs = nameof(basering);
+        link l_fork = "MPtcp:fork";
+        open(l_fork);
+        write(l_fork, quote(system("pid")));
+        int pid = read(l_fork);
+        write(l_fork, quote(timeStd(eval(i))));
+
+        // sleep in small intervalls for appr. one second
+        if (wait > 0)
+        {
+          while(j < 1000000)
+          {
+            if (status(l_fork, "read", "ready", j)) {break;}
+            j = j + j;
+          }
+        }
+        j = 1;
+        while (j < wait)
+        {
+          if (status(l_fork, "read", "ready", 1000000)) {break;}
+          j = j + 1;
+        }
+        if (status(l_fork, "read", "ready"))
+        {
+          def result = read(l_fork);
+          if (bs != nameof(basering))
+          {
+            def PP = basering;
+            setring P;
+            def result = imap(PP, result);
+            kill PP;
+          }
+          kill (l_fork);
+        }
+        else
+        {
+          ideal result=i;
+          j = system("sh", "kill " + string(pid));
+        }
+        return (result);
+      }
+    }
+  }
+  return(std(i));
+}
+example
+{ "EXAMPLE:"; echo = 2;
+   ring r=32003,(a,b,c,d,e),dp;
+   int n=6;
+   ideal i=
+   a^n-b^n,
+   b^n-c^n,
+   c^n-d^n,
+   d^n-e^n,
+   a^(n-1)*b+b^(n-1)*c+c^(n-1)*d+d^(n-1)*e+e^(n-1)*a;
+   timeStd(i,2);
+   timeStd(i,20);
+}
+
+proc factorH(poly p)
+"USAGE:  factorH(p)  p poly
+RETURN:  factorize(p)
+NOTE:    changes variables to become the last variable the principal
+         one in the multivariate factorization and factorizes then
+         the polynomial
+EXAMPLE: example factorH; shows an example
+"
+{
+   def R=basering;
+   int i,j;
+   int n=1;
+   int d=nrows(coeffs(p,var(1)));
+   for(i=1;i<=nvars(R);i++)
+   {
+      j=nrows(coeffs(p,var(i)));
+      if(d>j)
+      {
+         n=i;
+         d=j;
+      }
+   }
+   ideal ma=maxideal(1);    //die letzte Variable ist die Hauptvariable
+   ma[nvars(R)]=var(n);
+   ma[n]=var(nvars(R));
+   map phi=R,ma;
+   list fac=factorize(phi(p));
+   list re=phi(fac);
+   return(re);
+}
+example
+{ "EXAMPLE:"; echo = 2;
+  system("random",992851144);
+  ring r=32003,(x,y,z,w,t),lp;
+  poly p=y2w9+yz7t-yz5w4-z2w4t4-w8t3;
+  factorize(p);  //fast
+  system("random",992851262);
+  factorize(p);  //slow
+  system("random",992851262);
+  factorH(p);
+}
+
 /*
 proc minres(list #)