TSparseMtx.UpperTriangle Method

Summary

Extract upper part of the Mtx.

Declaration

Function UpperTriangle(Mtx: TSparseMtx; Diagonal: boolean = false): TSparseMtx;

Description

Copies only the upper triangular part of the Mtx sparse matrix. The result is stored in the calling sparse matrix. If the Diagonal boolean parameter is true then the Mtx matrix main diagonal elements will be copied to the calling matrix main diagonal elements. If the Diagonal parameter is false, the calling matrix main diagonal elements will be set to zero.

See Also
LowerTriangle

Example 1

          var asp, bsp: TSparseMtx;
            csp, dsp: TSparseMtx;
            d: Vector;
          begin
            // ...
            // #1 : split asp into lower(bsp), upper(csp) and diagonal(d) sections
            bsp.LowerTriangle(asp);
            csp.UpperTriangle(asp);
            asp.Diag(d);
            // now combine lower(bsp), upper, and diagonal(d) back
            dsp.AddSplit(bsp,d,csp);
            // should be equal
            if not asp.Equal(dsp) then Eraise('Not Equal!');
          end;