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blowUp2
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Author:  Susobhan [ Tue Mar 10, 2015 3:05 pm ]
Post subject:  blowUp2

Can someone help in Computing this example of a blow-up by hand? I want to see exactly how does the blow-up looks at affine chart.

LIB "resolve.lib";
ring r=0,(x,y,z),dp;
ideal I=z2-x^3*y^2;
ideal C=z,xy;
list li=blowUp2(I,C);
size(li); // number of charts
==> 2
def S1=li[1];
setring S1; // chart 1
basering;
==> // characteristic : 0
==> // number of vars : 3
==> // block 1 : ordering dp
==> // : names x(1) x(3) y(2)
==> // block 2 : ordering C
Jnew;
==> Jnew[1]=x(1)*y(2)^2-1
eD;
==> eD[1]=x(3)
==> eD[2]=x(1)*y(2)^2-1
bM;
==> bM[1]=x(1)
==> bM[2]=x(3)*y(2)^3
==> bM[3]=x(3)
def S2=li[2];
setring S2; // chart 2
basering;
==> // characteristic : 0
==> // number of vars : 2
==> // block 1 : ordering dp
==> // : names x(2) y(1)
==> // block 2 : ordering C
Jnew;
==> Jnew[1]=0
eD;
==> eD[1]=x(2)*y(1)^2
bM;
==> bM[1]=y(1)^2
==> bM[2]=x(2)
==> bM[3]=x(2)*y(1)^3

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