C C Parallel Sparse BLAS v2.0 C (C) Copyright 2006 Salvatore Filippone University of Rome Tor Vergata C Alfredo Buttari University of Rome Tor Vergata C C Redistribution and use in source and binary forms, with or without C modification, are permitted provided that the following conditions C are met: C 1. Redistributions of source code must retain the above copyright C notice, this list of conditions and the following disclaimer. C 2. Redistributions in binary form must reproduce the above copyright C notice, this list of conditions, and the following disclaimer in the C documentation and/or other materials provided with the distribution. C 3. The name of the PSBLAS group or the names of its contributors may C not be used to endorse or promote products derived from this C software without specific written permission. C C THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS C ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED C TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR C PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS C BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR C CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF C SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS C INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN C CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) C ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE C POSSIBILITY OF SUCH DAMAGE. C C *********************************************************************** * * * FUNCTION = This subroutine returns an array of pointers, L, * * to be used to sort the integer input vector K; * * the routine implements a list merge-sort * * * *********************************************************************** * * * CALL MRGSRTD(N,K,L,IRET) * * * * INPUT = * * * * SYMBOLIC NAME: N * * POSITION: First parameter. * * ATTRIBUTES: INTEGER * * VALUES: >= 0 * * DESCRIPTION: Dimension of the array to be sorted * * * * SYMBOLIC NAME: K * * POSITION: Second parameter * * ATTRIBUTES: INTEGER ARRAY(N) * * VALUES: Any * * DESCRIPTION: Input array containing the keys, i.e., values * * to be sorted * * * * * * * * OUTPUT = * * * * SYMBOLIC NAME: L * * POSITION: Third parameter * * ATTRIBUTES: INTEGER ARRAY(N+2) * * VALUES: >= 0 * * DESCRIPTION: On exit, this array contains pointers to * * the keys array. * * * *********************************************************************** *********************************************************************** * * *********************************************************************** *********************************************************************** * ALGORITHM DESCRIPTION * * * * REFERENCES = (1) D. E. Knuth * * The Art of Computer Programming, * * vol.3: Sorting and Searching * * Addison-Wesley, 1973 * * * * FUNCTION = This subroutine is based on the well-known merge-sort * * algorithm; according to (1) we are sorting 'records' * * R(I) with respect to keys K(I), and to this purpose * * we use 'links' L(I); at the end of the subroutine, * * L(0) is the index of the first record in the sorted * * sequence, then for every record R(I), we have into * * L(I) the index of the next one in the sequence. A * * value L(I)=0 signals the end of the sequence. * * The sorting is stable, i.e., if K(I)=K(J) and I