SCASUM(3)

SYNOPSIS
FUNCTION SCASUM (N, CX, INCX)

NAME
scasum - Compute the sum of the magnitudes of the real and imaginary elements of a complex vector.

LIBRARY
SLATEC (BLAS)

CATEGORY
D1A3A

TYPE
COMPLEX (SASUM-S, DASUM-D, SCASUM-C)

KEYWORDS
BLAS, LINEAR ALGEBRA, SUM OF MAGNITUDES OF A VECTOR

AUTHOR
Lawson, C. L., (JPL) Hanson, R. J., (SNLA) Kincaid, D. R., (U. of Texas) Krogh, F. T., (JPL)

DESCRIPTION
B L A S Subprogram Description of Parameters --Input-- N number of elements in input vector(s) CX complex vector with N elements INCX storage spacing between elements of CX --Output-- SCASUM single precision result (zero if N .LE. 0) Returns sums of magnitudes of real and imaginary parts of components of CX. Note that this is not the L1 norm of CX. CASUM = sum from 0 to N-1 of ABS(REAL(CX(IX+I*INCX))) + ABS(IMAG(CX(IX+I*INCX))), where IX = 1 if INCX .GE. 0, else IX = 1+(1-N)*INCX.

REFERENCES
C. L. Lawson, R. J. Hanson, D. R. Kincaid and F. T. Krogh, Basic linear algebra subprograms for Fortran usage, Algorithm No. 539, Transactions on Mathematical Software 5, 3 (September 1979), pp. 308-323.

ROUTINES CALLED
(NONE)

REVISION HISTORY (YYMMDD)
791001 DATE WRITTEN
890831 Modified array declarations. (WRB)
890831 REVISION DATE from Version 3.2
891214 Prologue converted to Version 4.0 format. (BAB)
900821 Modified to correct problem with a negative increment. (WRB)
920501 Reformatted the REFERENCES section. (WRB)