Goto Chapter: Top 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 Ind
 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 

10 Sparse Chain complexes

10 Sparse Chain complexes

SparseMat(A)

Inputs a matrix A and returns the matrix in sparse format.

TransposeOfSparseMat(A)

Inputs a sparse matrix A and returns its transpose sparse format.

ReverseSparseMat(A)

Inputs a sparse matrix A and modifies it by reversing the order of the columns. This function modifies A and returns no value.

SparseRowMult(A,i,k)

Multiplies the i-th row of a sparse matrix A by k. The sparse matrix A is modified but nothing is returned.

SparseRowInterchange(A,i,k)

Interchanges the i-th and j-th rows of a sparse matrix A by k. The sparse matrix A is modified but nothing is returned.

SparseRowAdd(A,i,j,k)

Adds k times the j-th row to the i-th row of a sparse matrix A. The sparse matrix A is modified but nothing is returned.

SparseSemiEchelon(A)

Converts a sparse matrix A to semi-echelon form (which means echelon form up to a permutation of rows). The sparse matrix A is modified but nothing is returned.

RankMatDestructive(A)

Returns the rank of a sparse matrix A. The sparse matrix A is modified during the calculation.

RankMat(A)

Returns the rank of a sparse matrix A.

SparseChainComplex(Y)

Inputs a regular CW-complex Y and returns a sparse chain complex which is chain homotopy equivalent to the cellular chain complex of Y. The function uses discrete vector fields to calculate a smallish chain complex.

SparseChainComplexOfRegularCWComplex(Y)

Inputs a regular CW-complex Y and returns its cellular chain complex as a sparse chain complex. The function SparseChainComplex(Y) will usually return a smaller chain complex.

SparseBoundaryMatrix(C,n)

Inputs a sparse chain complex C and integer n. Returns the n-th boundary matrix of the chain complex in sparse format.

Bettinumbers(C,n)

Inputs a sparse chain complex C and integer n. Returns the n-th Netti number of the chain complex.


 


 [Top of Book]  [Contents]   [Previous Chapter]   [Next Chapter] 
Goto Chapter: Top 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 Ind

generated by GAPDoc2HTML