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LinKerModP [OBSOLETE]

[OBSOLETE] find the kernel of a matrix mod p

Syntax
[OBSOLETE]

Description
[OBSOLETE] In CoCoA-4 it was difficult to map a matrix into ZZ/(p) . Now, in CoCoA-5, we can map the matrix and then call directly LinKer and LinKerBasis .

Example
/**/  use ZZ/(7);
/**/  M := mat([[1,2,3,4],[5,6,7,8],[9,10,11,12]]); --> by default over QQ
/**/  LinKerBasis(M);
[[-1, 2, -1, 0], [-2, 3, 0, -1]]

/**/  LinKerBasis(matrix(NewRingFp(3), M)); --> map M into ZZ/(3)
[[-1, -1, -1, 0], [1, 0, 0, -1]]

/**/  LinKer(matrix(CurrentRing, M)); --> map M into CurrentRing ZZ/(7)
matrix( /*RingWithID(9, "FFp(7)")*/
 [[-1, -2],
  [2, 3],
  [-1, 0],
  [0, -1]])
/**/  matrix(CurrentRing, M) * It;
matrix( /*RingWithID(9,"FFp(7)")*/
 [[0, 0],
  [0, 0],
  [0, 0]])

See Also