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tril -- Return the lower triangle

    call a%tril(l,info[,&
       & diag,imin,imax,jmin,jmax,rscale,cscale,u])

Returns the lower triangular part of submatrix A(imin:imax,jmin:jmax), optionally rescaling row/col indices to the range 1:imax-imin+1,1:jmax-jmin+1 and returing the complementary upper triangle.

Type:
Asynchronous.
On Entry
a
the sparse matrix.
A variable of type psb_Tspmat_type.
Scope: local.
diag
Include diagonals up to this one; diag=1 means the first superdiagonal, diag=-1 means the first subdiagonal. Default 0.
imin,imax,jmin,jmax
Minimum and maximum row and column indices.
Type: optional.
rscale,cscale
Whether to rescale row/column indices. Type: optional.
On Return
l
A copy of the lower triangle of a.
A variable of type psb_Tspmat_type.
u
(optional) A copy of the upper triangle of a.
A variable of type psb_Tspmat_type.
info
Return code.