Converts a vector-form distance vector to a square-form distance
matrix, and vice-versa.
Parameters :
X : ndarray
Either a condensed or redundant distance matrix.
Returns :
Y : ndarray
If a condensed distance matrix is passed, a redundant
one is returned, or if a redundant one is passed, a
condensed distance matrix is returned.
force :string
As with MATLAB(TM), if force is equal to ‘tovector’ or
‘tomatrix’, the input will be treated as a distance matrix
or distance vector respectively.
checks :bool
If checks is set to False, no checks will be made
for matrix symmetry nor zero diagonals. This is useful if
it is known that X-X.T1 is small and diag(X) is
close to zero. These values are ignored any way so they do
not disrupt the squareform transformation.