/*! @file dreadrb.c

 * \brief Read a matrix stored in Rutherford-Boeing format

 *

 * 

 * -- SuperLU routine (version 4.0) --

 * Lawrence Berkeley National Laboratory.

 * June 30, 2009

 * 

 *

 * Purpose

 * =======

 *

 * Read a DOUBLE PRECISION matrix stored in Rutherford-Boeing format 

 * as described below.

 *

 * Line 1 (A72, A8)

 *      Col. 1 - 72   Title (TITLE)

 *      Col. 73 - 80  Matrix name / identifier (MTRXID)

 *

 * Line 2 (I14, 3(1X, I13))

 *      Col. 1 - 14   Total number of lines excluding header (TOTCRD)

 *      Col. 16 - 28  Number of lines for pointers (PTRCRD)

 *      Col. 30 - 42  Number of lines for row (or variable) indices (INDCRD)

 *      Col. 44 - 56  Number of lines for numerical values (VALCRD)

 *

 * Line 3 (A3, 11X, 4(1X, I13))

 *      Col. 1 - 3    Matrix type (see below) (MXTYPE)

 *      Col. 15 - 28  Compressed Column: Number of rows (NROW)

 *                    Elemental: Largest integer used to index variable (MVAR)

 *      Col. 30 - 42  Compressed Column: Number of columns (NCOL)

 *                    Elemental: Number of element matrices (NELT)

 *      Col. 44 - 56  Compressed Column: Number of entries (NNZERO)

 *                    Elemental: Number of variable indeces (NVARIX)

 *      Col. 58 - 70  Compressed Column: Unused, explicitly zero

 *                    Elemental: Number of elemental matrix entries (NELTVL)

 *

 * Line 4 (2A16, A20)

 *      Col. 1 - 16   Fortran format for pointers (PTRFMT)

 *      Col. 17 - 32  Fortran format for row (or variable) indices (INDFMT)

 *      Col. 33 - 52  Fortran format for numerical values of coefficient matrix

 *                    (VALFMT)

 *                    (blank in the case of matrix patterns)

 *

 * The three character type field on line 3 describes the matrix type.

 * The following table lists the permitted values for each of the three

 * characters. As an example of the type field, RSA denotes that the matrix

 * is real, symmetric, and assembled.

 *

 * First Character:

 *      R Real matrix

 *      C Complex matrix

 *      I integer matrix

 *      P Pattern only (no numerical values supplied)

 *      Q Pattern only (numerical values supplied in associated auxiliary value

 *        file)

 *

 * Second Character:

 *      S Symmetric

 *      U Unsymmetric

 *      H Hermitian

 *      Z Skew symmetric

 *      R Rectangular

 *

 * Third Character:

 *      A Compressed column form

 *      E Elemental form

 *

 * 

 */

#include "slu_ddefs.h"

/*! \brief Eat up the rest of the current line */

static int dDumpLine(FILE *fp)

{

    register int c;

    while ((c = fgetc(fp)) != '\n') ;

    return 0;

}

static int dParseIntFormat(char *buf, int *num, int *size)

{

    char *tmp;

    tmp = buf;

    while (*tmp++ != '(') ;

    sscanf(tmp, "%d", num);

    while (*tmp != 'I' && *tmp != 'i') ++tmp;

    ++tmp;

    sscanf(tmp, "%d", size);

    return 0;

}

static int dParseFloatFormat(char *buf, int *num, int *size)

{

    char *tmp, *period;

    tmp = buf;

    while (*tmp++ != '(') ;

    *num = atoi(tmp); /*sscanf(tmp, "%d", num);*/

    while (*tmp != 'E' && *tmp != 'e' && *tmp != 'D' && *tmp != 'd'

           && *tmp != 'F' && *tmp != 'f') {

        /* May find kP before nE/nD/nF, like (1P6F13.6). In this case the

           num picked up refers to P, which should be skipped. */

        if (*tmp=='p' || *tmp=='P') {

           ++tmp;

           *num = atoi(tmp); /*sscanf(tmp, "%d", num);*/

        } else {

           ++tmp;

        }

    }

    ++tmp;

    period = tmp;

    while (*period != '.' && *period != ')') ++period ;

    *period = '\0';

    *size = atoi(tmp); /*sscanf(tmp, "%2d", size);*/

    return 0;

}

static int ReadVector(FILE *fp, int n, int *where, int perline, int persize)

{

    register int i, j, item;

    char tmp, buf[100];

    i = 0;

    while (i < n) {

        fgets(buf, 100, fp);    /* read a line at a time */

        for (j=0; j

            tmp = buf[(j+1)*persize];     /* save the char at that place */

            buf[(j+1)*persize] = 0;       /* null terminate */

            item = atoi(&buf[j*persize]); 

            buf[(j+1)*persize] = tmp;     /* recover the char at that place */

            where[i++] = item - 1;

        }

    }

    return 0;

}

static int dReadValues(FILE *fp, int n, double *destination, int perline,

        int persize)

{

    register int i, j, k, s;

    char tmp, buf[100];

    i = 0;

    while (i < n) {

        fgets(buf, 100, fp);    /* read a line at a time */

        for (j=0; j

            tmp = buf[(j+1)*persize];     /* save the char at that place */

            buf[(j+1)*persize] = 0;       /* null terminate */

            s = j*persize;

            for (k = 0; k < persize; ++k) /* No D_ format in C */

                if ( buf[s+k] == 'D' || buf[s+k] == 'd' ) buf[s+k] = 'E';

            destination[i++] = atof(&buf[s]);

            buf[(j+1)*persize] = tmp;     /* recover the char at that place */

        }

    }

    return 0;

}

void

dreadrb(int *nrow, int *ncol, int *nonz,

        double **nzval, int **rowind, int **colptr)

{

    register int i, numer_lines = 0;

    int tmp, colnum, colsize, rownum, rowsize, valnum, valsize;

    char buf[100], type[4];

    FILE *fp;

    fp = stdin;

    /* Line 1 */

    fgets(buf, 100, fp);

    fputs(buf, stdout);

    /* Line 2 */

    for (i=0; i<4; i++) {

        fscanf(fp, "%14c", buf); buf[14] = 0;

        sscanf(buf, "%d", &tmp);

        if (i == 3) numer_lines = tmp;

    }

    dDumpLine(fp);

    /* Line 3 */

    fscanf(fp, "%3c", type);

    fscanf(fp, "%11c", buf); /* pad */

    type[3] = 0;

#ifdef DEBUG

    printf("Matrix type %s\n", type);

#endif

    fscanf(fp, "%14c", buf); sscanf(buf, "%d", nrow);

    fscanf(fp, "%14c", buf); sscanf(buf, "%d", ncol);

    fscanf(fp, "%14c", buf); sscanf(buf, "%d", nonz);

    fscanf(fp, "%14c", buf); sscanf(buf, "%d", &tmp);

    if (tmp != 0)

        printf("This is not an assembled matrix!\n");

    if (*nrow != *ncol)

        printf("Matrix is not square.\n");

    dDumpLine(fp);

    /* Allocate storage for the three arrays ( nzval, rowind, colptr ) */

    dallocateA(*ncol, *nonz, nzval, rowind, colptr);

    /* Line 4: format statement */

    fscanf(fp, "%16c", buf);

    dParseIntFormat(buf, &colnum, &colsize);

    fscanf(fp, "%16c", buf);

    dParseIntFormat(buf, &rownum, &rowsize);

    fscanf(fp, "%20c", buf);

    dParseFloatFormat(buf, &valnum, &valsize);

    dDumpLine(fp);

#ifdef DEBUG

    printf("%d rows, %d nonzeros\n", *nrow, *nonz);

    printf("colnum %d, colsize %d\n", colnum, colsize);

    printf("rownum %d, rowsize %d\n", rownum, rowsize);

    printf("valnum %d, valsize %d\n", valnum, valsize);

#endif

    ReadVector(fp, *ncol+1, *colptr, colnum, colsize);

    ReadVector(fp, *nonz, *rowind, rownum, rowsize);

    if ( numer_lines ) {

        dReadValues(fp, *nonz, *nzval, valnum, valsize);

    }

    fclose(fp);

}