dsdot(l)

1DSDOT(1)                         BLAS routine                         DSDOT(1)
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NAME

6       DSDOT - and result
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SYNOPSIS

9       DOUBLE PRECISION FUNCTION DSDOT(N,SX,INCX,SY,INCY)
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11           INTEGER      INCX,INCY,N
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13           REAL         SX(*),SY(*)
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PURPOSE

16       precision accumulation and result.
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18       Returns  D.P. dot product accumulated in D.P., for S.P. SX and SY DSDOT
19       = sum for I = 0 to N-1 of  SX(LX+I*INCX) * SY(LY+I*INCY), where LX =  1
20       if  INCX .GE. 0, else LX = 1+(1-N)*INCX, and LY is defined in a similar
21       way using INCY.
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ARGUMENTS

25       N      (input) INTEGER
26              number of elements in input vector(s)
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28       SX     (input) REAL array, dimension(N)
29              single precision vector with N elements
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31       INCX   (input) INTEGER
32              storage spacing between elements of SX
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34       SY     (input) REAL array, dimension(N)
35              single precision vector with N elements
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37       INCY   (input) INTEGER
38              storage spacing between elements of SY
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40       DSDOT  (output) DOUBLE PRECISION
41              DSDOT  double precision dot product (zero if N.LE.0)
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43              REFERENCES ========== C. L. Lawson, R. J. Hanson, D. R.  Kincaid
44              and  F.  T.  Krogh, Basic linear algebra subprograms for Fortran
45              usage, Algorithm No. 539, Transactions on Mathematical  Software
46              5, 3 (September 1979), pp. 308-323.
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48              REVISION HISTORY  (YYMMDD) ==========================
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50       791001  DATE WRITTEN
51               890831   Modified  array  declarations.  (WRB) 890831  REVISION
52               DATE from Version 3.2 891214  Prologue converted to Version 4.0
53               format.   (BAB)  920310  Corrected definition of LX in DESCRIP‐
54               TION.  (WRB) 920501  Reformatted the REFERENCES section.  (WRB)
55               070118  Reformat to LAPACK style (JL)
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59BLAS routine                     February 2007                        DSDOT(1)