.TH "single_blas_level1" 3 "Sun Nov 27 2022" "Version 3.11.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
single_blas_level1 \- real
.SH SYNOPSIS
.br
.PP
.SS "Functions"

.in +1c
.ti -1c
.RI "real function \fBsasum\fP (N, SX, INCX)"
.br
.RI "\fBSASUM\fP "
.ti -1c
.RI "subroutine \fBsaxpy\fP (N, SA, SX, INCX, SY, INCY)"
.br
.RI "\fBSAXPY\fP "
.ti -1c
.RI "real function \fBscabs1\fP (Z)"
.br
.RI "\fBSCABS1\fP "
.ti -1c
.RI "real function \fBscasum\fP (N, CX, INCX)"
.br
.RI "\fBSCASUM\fP "
.ti -1c
.RI "subroutine \fBscopy\fP (N, SX, INCX, SY, INCY)"
.br
.RI "\fBSCOPY\fP "
.ti -1c
.RI "real function \fBsdot\fP (N, SX, INCX, SY, INCY)"
.br
.RI "\fBSDOT\fP "
.ti -1c
.RI "real function \fBsdsdot\fP (N, SB, SX, INCX, SY, INCY)"
.br
.RI "\fBSDSDOT\fP "
.ti -1c
.RI "subroutine \fBsrot\fP (N, SX, INCX, SY, INCY, C, S)"
.br
.RI "\fBSROT\fP "
.ti -1c
.RI "subroutine \fBsrotm\fP (N, SX, INCX, SY, INCY, SPARAM)"
.br
.RI "\fBSROTM\fP "
.ti -1c
.RI "subroutine \fBsrotmg\fP (SD1, SD2, SX1, SY1, SPARAM)"
.br
.RI "\fBSROTMG\fP "
.ti -1c
.RI "subroutine \fBsscal\fP (N, SA, SX, INCX)"
.br
.RI "\fBSSCAL\fP "
.ti -1c
.RI "subroutine \fBsswap\fP (N, SX, INCX, SY, INCY)"
.br
.RI "\fBSSWAP\fP "
.in -1c
.SH "Detailed Description"
.PP 
This is the group of real LEVEL 1 BLAS routines\&. 
.SH "Function Documentation"
.PP 
.SS "real function sasum (integer N, real, dimension(*) SX, integer INCX)"

.PP
\fBSASUM\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SASUM takes the sum of the absolute values\&.
    uses unrolled loops for increment equal to one\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 3/93 to return if incx \&.le\&. 0\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "subroutine saxpy (integer N, real SA, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY)"

.PP
\fBSAXPY\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SAXPY constant times a vector plus a vector\&.
    uses unrolled loops for increments equal to one\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISA\fP 
.PP
.nf
          SA is REAL
           On entry, SA specifies the scalar alpha\&.
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "real function scabs1 (complex Z)"

.PP
\fBSCABS1\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
 SCABS1 computes |Re(\&.)| + |Im(\&.)| of a complex number
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIZ\fP 
.PP
.nf
          Z is COMPLEX
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP

.SS "real function scasum (integer N, complex, dimension(*) CX, integer INCX)"

.PP
\fBSCASUM\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SCASUM takes the sum of the (|Re(\&.)| + |Im(\&.)|)'s of a complex vector and
    returns a single precision result\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fICX\fP 
.PP
.nf
          CX is COMPLEX array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 3/93 to return if incx \&.le\&. 0\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "subroutine scopy (integer N, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY)"

.PP
\fBSCOPY\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SCOPY copies a vector, x, to a vector, y\&.
    uses unrolled loops for increments equal to 1\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "real function sdot (integer N, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY)"

.PP
\fBSDOT\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SDOT forms the dot product of two vectors\&.
    uses unrolled loops for increments equal to one\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "real function sdsdot (integer N, real SB, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY)"

.PP
\fBSDSDOT\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
   Compute the inner product of two vectors with extended
   precision accumulation\&.

   Returns S\&.P\&. result with dot product accumulated in D\&.P\&.
   SDSDOT = SB + 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\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
          number of elements in input vector(s)
.fi
.PP
.br
\fISB\fP 
.PP
.nf
          SB is REAL
          single precision scalar to be added to inner product
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
          single precision vector with N elements
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
          storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
          single precision vector with N elements
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
          storage spacing between elements of SY
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Lawson, C\&. L\&., (JPL), Hanson, R\&. J\&., (SNLA), 
.PP
Kincaid, D\&. R\&., (U\&. of Texas), Krogh, F\&. T\&., (JPL) 
.PP
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
    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)

    791001  DATE WRITTEN
    890531  Changed all specific intrinsics to generic\&.  (WRB)
    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 coding style
.fi
.PP
 
.RE
.PP

.SS "subroutine srot (integer N, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY, real C, real S)"

.PP
\fBSROT\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    applies a plane rotation\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
.br
\fIC\fP 
.PP
.nf
          C is REAL
.fi
.PP
.br
\fIS\fP 
.PP
.nf
          S is REAL
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "subroutine srotm (integer N, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY, real, dimension(5) SPARAM)"

.PP
\fBSROTM\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX

    (SX**T) , WHERE **T INDICATES TRANSPOSE\&. THE ELEMENTS OF SX ARE IN
    (SX**T)

    SX(LX+I*INCX), I = 0 TO N-1, WHERE LX = 1 IF INCX \&.GE\&. 0, ELSE
    LX = (-INCX)*N, AND SIMILARLY FOR SY USING USING LY AND INCY\&.
    WITH SPARAM(1)=SFLAG, H HAS ONE OF THE FOLLOWING FORMS\&.\&.

    SFLAG=-1\&.E0     SFLAG=0\&.E0        SFLAG=1\&.E0     SFLAG=-2\&.E0

      (SH11  SH12)    (1\&.E0  SH12)    (SH11  1\&.E0)    (1\&.E0  0\&.E0)
    H=(          )    (          )    (          )    (          )
      (SH21  SH22),   (SH21  1\&.E0),   (-1\&.E0 SH22),   (0\&.E0  1\&.E0)\&.
    SEE  SROTMG FOR A DESCRIPTION OF DATA STORAGE IN SPARAM\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
.br
\fISPARAM\fP 
.PP
.nf
          SPARAM is REAL array, dimension (5)
     SPARAM(1)=SFLAG
     SPARAM(2)=SH11
     SPARAM(3)=SH21
     SPARAM(4)=SH12
     SPARAM(5)=SH22
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP

.SS "subroutine srotmg (real SD1, real SD2, real SX1, real SY1, real, dimension(5) SPARAM)"

.PP
\fBSROTMG\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    CONSTRUCT THE MODIFIED GIVENS TRANSFORMATION MATRIX H WHICH ZEROS
    THE SECOND COMPONENT OF THE 2-VECTOR  (SQRT(SD1)*SX1,SQRT(SD2)*>    SY2)**T\&.
    WITH SPARAM(1)=SFLAG, H HAS ONE OF THE FOLLOWING FORMS\&.\&.

    SFLAG=-1\&.E0     SFLAG=0\&.E0        SFLAG=1\&.E0     SFLAG=-2\&.E0

      (SH11  SH12)    (1\&.E0  SH12)    (SH11  1\&.E0)    (1\&.E0  0\&.E0)
    H=(          )    (          )    (          )    (          )
      (SH21  SH22),   (SH21  1\&.E0),   (-1\&.E0 SH22),   (0\&.E0  1\&.E0)\&.
    LOCATIONS 2-4 OF SPARAM CONTAIN SH11,SH21,SH12, AND SH22
    RESPECTIVELY\&. (VALUES OF 1\&.E0, -1\&.E0, OR 0\&.E0 IMPLIED BY THE
    VALUE OF SPARAM(1) ARE NOT STORED IN SPARAM\&.)

    THE VALUES OF GAMSQ AND RGAMSQ SET IN THE DATA STATEMENT MAY BE
    INEXACT\&.  THIS IS OK AS THEY ARE ONLY USED FOR TESTING THE SIZE
    OF SD1 AND SD2\&.  ALL ACTUAL SCALING OF DATA IS DONE USING GAM\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fISD1\fP 
.PP
.nf
          SD1 is REAL
.fi
.PP
.br
\fISD2\fP 
.PP
.nf
          SD2 is REAL
.fi
.PP
.br
\fISX1\fP 
.PP
.nf
          SX1 is REAL
.fi
.PP
.br
\fISY1\fP 
.PP
.nf
          SY1 is REAL
.fi
.PP
.br
\fISPARAM\fP 
.PP
.nf
          SPARAM is REAL array, dimension (5)
     SPARAM(1)=SFLAG
     SPARAM(2)=SH11
     SPARAM(3)=SH21
     SPARAM(4)=SH12
     SPARAM(5)=SH22
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP

.SS "subroutine sscal (integer N, real SA, real, dimension(*) SX, integer INCX)"

.PP
\fBSSCAL\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SSCAL scales a vector by a constant\&.
    uses unrolled loops for increment equal to 1\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISA\fP 
.PP
.nf
          SA is REAL
           On entry, SA specifies the scalar alpha\&.
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 3/93 to return if incx \&.le\&. 0\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SS "subroutine sswap (integer N, real, dimension(*) SX, integer INCX, real, dimension(*) SY, integer INCY)"

.PP
\fBSSWAP\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    SSWAP interchanges two vectors\&.
    uses unrolled loops for increments equal to 1\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBFurther Details:\fP
.RS 4

.PP
.nf
     jack dongarra, linpack, 3/11/78\&.
     modified 12/3/93, array(1) declarations changed to array(*)
.fi
.PP
 
.RE
.PP

.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.