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PencilsOfQuadrics :: yAction

yAction -- defines a vector bundle on E

Synopsis

Description

A matrix representing the action of y for the hyperelliptic curve E with equation y^2 - (-1)^g * f.

i1 : kk = ZZ/101;
i2 : R = kk[s,t];
i3 : f = (s+2*t)*(s+t)*(s-t)*(s-2*t);
i4 : L0 = randomLineBundle(0,f)

o4 = VectorBundleOnE{...1...}

o4 : VectorBundleOnE
i5 : M = L0.yAction

o5 = {-1} | -29s2+19st+19t2 38s2+9st+47t2  |
     {-1} | 47s2-22st+t2    29s2-19st-19t2 |

             2       2
o5 : Matrix R  <--- R
i6 : M^2 - f*id_(source M)

o6 = 0

             2       2
o6 : Matrix R  <--- R

See also

For the programmer

The object yAction is a symbol.