.TH DSDOT 1 "February 2007" "BLAS routine" "BLAS routine" .SH NAME DSDOT - and result .SH SYNOPSIS .TP 17 DOUBLE PRECISION FUNCTION DSDOT(N,SX,INCX,SY,INCY) .TP 17 .ti +4 INTEGER INCX,INCY,N .TP 17 .ti +4 REAL SX(*),SY(*) .SH PURPOSE precision accumulation and result. Returns D.P. dot product accumulated in D.P., for S.P. SX and SY DSDOT = sum for I = 0 to N-1 of SX(LX+I*INCX) * SY(LY+I*INCY), where LX = 1 if INCX .GE. 0, else LX = 1+(1-N)*INCX, and LY is defined in a similar way using INCY. .br .SH ARGUMENTS .TP 7 N (input) INTEGER number of elements in input vector(s) .TP 7 SX (input) REAL array, dimension(N) single precision vector with N elements .TP 7 INCX (input) INTEGER storage spacing between elements of SX .TP 7 SY (input) REAL array, dimension(N) single precision vector with N elements .TP 7 INCY (input) INTEGER storage spacing between elements of SY .TP 7 DSDOT (output) DOUBLE PRECISION DSDOT double precision dot product (zero if N.LE.0) 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. REVISION HISTORY (YYMMDD) ========================== .TP 8 791001 DATE WRITTEN 890831 Modified array declarations. (WRB) 890831 REVISION DATE from Version 3.2 891214 Prologue converted to Version 4.0 format. (BAB) 920310 Corrected definition of LX in DESCRIPTION. (WRB) 920501 Reformatted the REFERENCES section. (WRB) 070118 Reformat to LAPACK style (JL)