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ArrDerModule    --    set of generators of the module of logarithmic derivations of an arrangement of hyperplanes


Syntax 
ArrDerModule(Q: RINGELEM): MAT

Description
This function returns the matrix whose columns are a set of generators of the module of logarithmic derivations of an arrangement of hyperplanes described by its defining equation Q.

Example 
/**/ use QQ[x,y];	
/**/ A := [x, x-y, y];
/**/ Q_A := product(A);	
/**/ ArrDerModule(Q_A);
matrix( /*RingWithID(70, "QQ[x,y]")*/
 [[x,  0],
  [y,  x*y -y^2]])

/**/ use QQ[x,y,z];
/**/ A := [x, x+z, y, 2*y-3*z];
/**/ ArrDerModule(product(A));
matrix( /*RingWithID(78, "QQ[x,y,z]")*/
 [[x,  0,  0,  0],
  [y,  y^2 +(-3/2)*y*z,  0,  x*y +y*z],
  [z,  0,  x*y +(-3/2)*x*z +y*z +(-3/2)*z^2,  x*z +z^2]])

See Also