source:
git/Tst/Manual/proximitymatrix.tst
@
0d6b7fc
Last change on this file since 0d6b7fc was 894057, checked in by , 13 years ago | |
---|---|
|
|
File size: 931 bytes |
Line | |
---|---|
1 | LIB "tst.lib"; tst_init(); |
2 | LIB "alexpoly.lib"; |
3 | ring r=0,(x,y),ls; |
4 | poly f1=(y2-x3)^2-4x5y-x7; |
5 | poly f2=y2-x3; |
6 | poly f3=y3-x2; |
7 | list proximity=proximitymatrix(f1*f2*f3); |
8 | /// The proximity matrix P /// |
9 | print(proximity[1]); |
10 | /// The proximity resolution graph N /// |
11 | print(proximity[2]); |
12 | /// They satisfy N=-transpose(P)*P /// |
13 | print(-transpose(proximity[1])*proximity[1]); |
14 | /// The incidence matrix of the Enriques diagram /// |
15 | print(proximity[3]); |
16 | /// If M is the matrix of multiplicities and TM the matrix of total |
17 | /// multiplicities of the singularity, then M=P*TM. |
18 | /// We therefore calculate the (total) multiplicities. Note that |
19 | /// they have to be slightly extended. |
20 | list MULT=extend_multiplicities(totalmultiplicities(f1*f2*f3)); |
21 | intmat TM=MULT[1]; // Total multiplicites. |
22 | intmat M=MULT[2]; // Multiplicities. |
23 | /// Check: M-P*TM=0. |
24 | M-proximity[1]*TM; |
25 | /// Check: inverse(P)*M-TM=0. |
26 | intmat_inverse(proximity[1])*M-TM; |
27 | tst_status(1);$ |
Note: See TracBrowser
for help on using the repository browser.