function a = i4col_sort_a ( m, n, a ) %*****************************************************************************80 % %% I4COL_SORT_A ascending sorts an I4COL. % % Discussion: % % In lexicographic order, the statement "X < Y", applied to two real % vectors X and Y of length M, means that there is some index I, with % 1 <= I <= M, with the property that % % X(J) = Y(J) for J < I, % and % X(I) < Y(I). % % In other words, the first time they differ, X is smaller. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 20 February 2005 % % Author: % % John Burkardt % % Parameters: % % Input, integer M, the number of rows of A, and the length of % a vector of data. % % Input, integer N, the number of columns of A. % % Input, integer A(M,N), the array of N columns of M-vectors. % % Output, integer A(M,N), the columns of A have been sorted in ascending % lexicographic order. % if ( m <= 0 ) return end if ( n <= 1 ) return end % % Initialize. % i = 0; indx = 0; isgn = 0; j = 0; % % Call the external heap sorter. % while ( 1 ) [ indx, i, j ] = sort_heap_external ( n, indx, isgn ); % % Interchange the I and J objects. % if ( 0 < indx ) a = i4col_swap ( m, n, a, i, j ); % % Compare the I and J objects. % elseif ( indx < 0 ) isgn = i4col_compare ( m, n, a, i, j ); elseif ( indx == 0 ) break end end return end