FlexMatrix{T}(rows,cols) creates a new FlexMatrix with rows indexed by rows, columns indexed by cols and all zero entries of type T (which is Number if omitted).

FlexMatrix(v::FlexVector) converts v into a one-column FlexMatrix whose sole column index is Int(1)

FlexVector{T}(idx) creates a new FlexVector with entries indexed by idx filled with zeros of type T (which defaults to Number)

FlexConvert(vec) converts the vector vec into a FlexVector.

FlexOnes(T,dom) creates an all 1s vector indexed by dom. If T is missing, values default to Float64.

col_keys(M::FlexMatrix) returns a list of the keys to the columns of M.

delete_col!(A,c) deletes row c from the FlexMatrixA.

delete_entry!(v,x) deletes the entry indexed by x in the FlexVectorx.

delete_row!(A,r) deletes row r from the FlexMatrixA.

row_keys(M::FlexMatrix) returns a list of the keys to the rows of M.