Changeset 352a84b in git for Tst/Short/bug_259.tst

Timestamp:

Feb 1, 2017, 4:17:04 PM (7 years ago)

Author:

Hans Schoenemann <hannes@…>

Branches:

(u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')

Children:

7d44dd5555e888e65ba7e20c25fc77d0d98f0db1

Parents:

4230277da20a55a572267a2d3ae8e860ffb8deee

Message:

test for bug tr. #259 extended (genus)

File:

• Tst/Short/bug_259.tst (modified) (1 diff)

Tst/Short/bug_259.tst

@@ -46 +46 @@
 }
 
+// Any plane curve consisting of d rational components has genus 1-d.
+// We study a nodal cubic, combined with 3 resp. 4 lines.
+// The genus then has to be -3 resp. -4
+ring rdp = 0,(x,y),dp;
+poly NC = (3*x^2*y+4*y^3-x^2-3*y+1);   // nodal cubic
+genus(NC);      // 0
+poly F = (x-1) * (x+1) * (3*y-1)* NC;  // 3A_5 + 4A_1
+genus(F);     // -3
+genus(F*y);   // -4
+genus(F/(x-1));  // -2
+genus(F/(x-1)*y);  // -3
+genus(F*(y+1));  // -4
+genus(F*(y+x));  // -4
+
 tst_status(1); $