Visible to Intel only — GUID: GUID-0573DD31-CB9D-45DF-9F74-E8E978AB9ECF
Visible to Intel only — GUID: GUID-0573DD31-CB9D-45DF-9F74-E8E978AB9ECF
?largv
Generates a vector of plane rotations with real cosines and real/complex sines.
Syntax
call slargv( n, x, incx, y, incy, c, incc )
call dlargv( n, x, incx, y, incy, c, incc )
call clargv( n, x, incx, y, incy, c, incc )
call zlargv( n, x, incx, y, incy, c, incc )
Include Files
- mkl.fi
Description
The routine generates a vector of real/complex plane rotations with real cosines, determined by elements of the real/complex vectors x and y.
For slargv/dlargv:
![Equation](/content/dam/docs/us/en/developer-reference-fortran/2023-2/162C321C-D474-46AF-A554-0E30C5FD7AD0-low.gif)
For clargv/zlargv:
![Equation](/content/dam/docs/us/en/developer-reference-fortran/2023-2/A3233C5F-0EB2-4ABE-BF13-0228624F6B13-low.jpg)
where c(i)2 + abs(s(i))2 = 1 and the following conventions are used (these are the same as in clartg/zlartg but differ from the BLAS Level 1 routine crotg/zrotg):
If yi = 0, then c(i) = 1 and s(i) = 0;
If xi = 0, then c(i) = 0 and s(i) is chosen so that ri is real.
Input Parameters
- n
-
INTEGER. The number of plane rotations to be generated.
- x, y
-
REAL for slargv
DOUBLE PRECISION for dlargv
COMPLEX for clargv
DOUBLE COMPLEX for zlargv
Arrays, DIMENSION (1+(n-1)*incx) and (1+(n-1)*incy), respectively. On entry, the vectors x and y.
- incx
-
INTEGER. The increment between elements of x.
incx > 0.
- incy
-
INTEGER. The increment between elements of y.
incy > 0.
- incc
-
INTEGER. The increment between elements of the output array c. incc > 0.
Output Parameters
- x
-
On exit, x(i) is overwritten by ai (for real flavors), or by ri (for complex flavors), for i = 1,...,n.
- y
-
On exit, the sines s(i) of the plane rotations.
- c
-
REAL for slargv/clargv
DOUBLE PRECISION for dlargv/zlargv
Array, DIMENSION (1+(n-1)*incc). The cosines of the plane rotations.