#include "clapack.h" /* Subroutine */ int slascl_(char *type__, integer *kl, integer *ku, real * cfrom, real *cto, integer *m, integer *n, real *a, integer *lda, integer *info) { /* System generated locals */ integer a_dim1, a_offset, i__1, i__2, i__3, i__4, i__5; /* Local variables */ integer i__, j, k1, k2, k3, k4; real mul, cto1; logical done; real ctoc; extern logical lsame_(char *, char *); integer itype; real cfrom1; extern doublereal slamch_(char *); real cfromc; extern /* Subroutine */ int xerbla_(char *, integer *); real bignum, smlnum; /* -- LAPACK auxiliary routine (version 3.1) -- */ /* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */ /* November 2006 */ /* .. Scalar Arguments .. */ /* .. */ /* .. Array Arguments .. */ /* .. */ /* Purpose */ /* ======= */ /* SLASCL multiplies the M by N real matrix A by the real scalar */ /* CTO/CFROM. This is done without over/underflow as long as the final */ /* result CTO*A(I,J)/CFROM does not over/underflow. TYPE specifies that */ /* A may be full, upper triangular, lower triangular, upper Hessenberg, */ /* or banded. */ /* Arguments */ /* ========= */ /* TYPE (input) CHARACTER*1 */ /* TYPE indices the storage type of the input matrix. */ /* = 'G': A is a full matrix. */ /* = 'L': A is a lower triangular matrix. */ /* = 'U': A is an upper triangular matrix. */ /* = 'H': A is an upper Hessenberg matrix. */ /* = 'B': A is a symmetric band matrix with lower bandwidth KL */ /* and upper bandwidth KU and with the only the lower */ /* half stored. */ /* = 'Q': A is a symmetric band matrix with lower bandwidth KL */ /* and upper bandwidth KU and with the only the upper */ /* half stored. */ /* = 'Z': A is a band matrix with lower bandwidth KL and upper */ /* bandwidth KU. */ /* KL (input) INTEGER */ /* The lower bandwidth of A. Referenced only if TYPE = 'B', */ /* 'Q' or 'Z'. */ /* KU (input) INTEGER */ /* The upper bandwidth of A. Referenced only if TYPE = 'B', */ /* 'Q' or 'Z'. */ /* CFROM (input) REAL */ /* CTO (input) REAL */ /* The matrix A is multiplied by CTO/CFROM. A(I,J) is computed */ /* without over/underflow if the final result CTO*A(I,J)/CFROM */ /* can be represented without over/underflow. CFROM must be */ /* nonzero. */ /* M (input) INTEGER */ /* The number of rows of the matrix A. M >= 0. */ /* N (input) INTEGER */ /* The number of columns of the matrix A. N >= 0. */ /* A (input/output) REAL array, dimension (LDA,N) */ /* The matrix to be multiplied by CTO/CFROM. See TYPE for the */ /* storage type. */ /* LDA (input) INTEGER */ /* The leading dimension of the array A. LDA >= max(1,M). */ /* INFO (output) INTEGER */ /* 0 - successful exit */ /* <0 - if INFO = -i, the i-th argument had an illegal value. */ /* ===================================================================== */ /* .. Parameters .. */ /* .. */ /* .. Local Scalars .. */ /* .. */ /* .. External Functions .. */ /* .. */ /* .. Intrinsic Functions .. */ /* .. */ /* .. External Subroutines .. */ /* .. */ /* .. Executable Statements .. */ /* Test the input arguments */ /* Parameter adjustments */ a_dim1 = *lda; a_offset = 1 + a_dim1; a -= a_offset; /* Function Body */ *info = 0; if (lsame_(type__, "G")) { itype = 0; } else if (lsame_(type__, "L")) { itype = 1; } else if (lsame_(type__, "U")) { itype = 2; } else if (lsame_(type__, "H")) { itype = 3; } else if (lsame_(type__, "B")) { itype = 4; } else if (lsame_(type__, "Q")) { itype = 5; } else if (lsame_(type__, "Z")) { itype = 6; } else { itype = -1; } if (itype == -1) { *info = -1; } else if (*cfrom == 0.f) { *info = -4; } else if (*m < 0) { *info = -6; } else if (*n < 0 || itype == 4 && *n != *m || itype == 5 && *n != *m) { *info = -7; } else if (itype <= 3 && *lda < max(1,*m)) { *info = -9; } else if (itype >= 4) { /* Computing MAX */ i__1 = *m - 1; if (*kl < 0 || *kl > max(i__1,0)) { *info = -2; } else /* if(complicated condition) */ { /* Computing MAX */ i__1 = *n - 1; if (*ku < 0 || *ku > max(i__1,0) || (itype == 4 || itype == 5) && *kl != *ku) { *info = -3; } else if (itype == 4 && *lda < *kl + 1 || itype == 5 && *lda < * ku + 1 || itype == 6 && *lda < (*kl << 1) + *ku + 1) { *info = -9; } } } if (*info != 0) { i__1 = -(*info); xerbla_("SLASCL", &i__1); return 0; } /* Quick return if possible */ if (*n == 0 || *m == 0) { return 0; } /* Get machine parameters */ smlnum = slamch_("S"); bignum = 1.f / smlnum; cfromc = *cfrom; ctoc = *cto; L10: cfrom1 = cfromc * smlnum; cto1 = ctoc / bignum; if (dabs(cfrom1) > dabs(ctoc) && ctoc != 0.f) { mul = smlnum; done = FALSE_; cfromc = cfrom1; } else if (dabs(cto1) > dabs(cfromc)) { mul = bignum; done = FALSE_; ctoc = cto1; } else { mul = ctoc / cfromc; done = TRUE_; } if (itype == 0) { /* Full matrix */ i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = *m; for (i__ = 1; i__ <= i__2; ++i__) { a[i__ + j * a_dim1] *= mul; /* L20: */ } /* L30: */ } } else if (itype == 1) { /* Lower triangular matrix */ i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = *m; for (i__ = j; i__ <= i__2; ++i__) { a[i__ + j * a_dim1] *= mul; /* L40: */ } /* L50: */ } } else if (itype == 2) { /* Upper triangular matrix */ i__1 = *n; for (j = 1; j <= i__1; ++j) { i__2 = min(j,*m); for (i__ = 1; i__ <= i__2; ++i__) { a[i__ + j * a_dim1] *= mul; /* L60: */ } /* L70: */ } } else if (itype == 3) { /* Upper Hessenberg matrix */ i__1 = *n; for (j = 1; j <= i__1; ++j) { /* Computing MIN */ i__3 = j + 1; i__2 = min(i__3,*m); for (i__ = 1; i__ <= i__2; ++i__) { a[i__ + j * a_dim1] *= mul; /* L80: */ } /* L90: */ } } else if (itype == 4) { /* Lower half of a symmetric band matrix */ k3 = *kl + 1; k4 = *n + 1; i__1 = *n; for (j = 1; j <= i__1; ++j) { /* Computing MIN */ i__3 = k3, i__4 = k4 - j; i__2 = min(i__3,i__4); for (i__ = 1; i__ <= i__2; ++i__) { a[i__ + j * a_dim1] *= mul; /* L100: */ } /* L110: */ } } else if (itype == 5) { /* Upper half of a symmetric band matrix */ k1 = *ku + 2; k3 = *ku + 1; i__1 = *n; for (j = 1; j <= i__1; ++j) { /* Computing MAX */ i__2 = k1 - j; i__3 = k3; for (i__ = max(i__2,1); i__ <= i__3; ++i__) { a[i__ + j * a_dim1] *= mul; /* L120: */ } /* L130: */ } } else if (itype == 6) { /* Band matrix */ k1 = *kl + *ku + 2; k2 = *kl + 1; k3 = (*kl << 1) + *ku + 1; k4 = *kl + *ku + 1 + *m; i__1 = *n; for (j = 1; j <= i__1; ++j) { /* Computing MAX */ i__3 = k1 - j; /* Computing MIN */ i__4 = k3, i__5 = k4 - j; i__2 = min(i__4,i__5); for (i__ = max(i__3,k2); i__ <= i__2; ++i__) { a[i__ + j * a_dim1] *= mul; /* L140: */ } /* L150: */ } } if (! done) { goto L10; } return 0; /* End of SLASCL */ } /* slascl_ */