largv - largv: generate vector of plane rotations

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subroutineclargv(integern,complex,dimension(*)x,integerincx,complex,dimension(*)y,integerincy,real,dimension(*)c,integerincc)CLARGV generates a vector of plane rotations with real cosines and complex sines. Purpose: CLARGV generates a vector of complex plane rotations with real cosines, determined by elements of the complex vectors x and y. For i = 1,2,...,n ( c(i) s(i) ) ( x(i) ) = ( r(i) ) ( -conjg(s(i)) c(i) ) ( y(i) ) = ( 0 ) where c(i)**2 + ABS(s(i))**2 = 1 The following conventions are used (these are the same as in CLARTG, but differ from the BLAS1 routine CROTG): If y(i)=0, then c(i)=1 and s(i)=0. If x(i)=0, then c(i)=0 and s(i) is chosen so that r(i) is real. ParametersN N is INTEGER The number of plane rotations to be generated. X X is COMPLEX array, dimension (1+(N-1)*INCX) On entry, the vector x. On exit, x(i) is overwritten by r(i), for i = 1,...,n. INCX INCX is INTEGER The increment between elements of X. INCX > 0. Y Y is COMPLEX array, dimension (1+(N-1)*INCY) On entry, the vector y. On exit, the sines of the plane rotations. INCY INCY is INTEGER The increment between elements of Y. INCY > 0. C C is REAL array, dimension (1+(N-1)*INCC) The cosines of the plane rotations. INCC INCC is INTEGER The increment between elements of C. INCC > 0. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. FurtherDetails: 6-6-96 - Modified with a new algorithm by W. Kahan and J. Demmel This version has a few statements commented out for thread safety (machine parameters are computed on each entry). 10 feb 03, SJH. subroutinedlargv(integern,doubleprecision,dimension(*)x,integerincx,doubleprecision,dimension(*)y,integerincy,doubleprecision,dimension(*)c,integerincc)DLARGV generates a vector of plane rotations with real cosines and real sines. Purpose: DLARGV generates a vector of real plane rotations, determined by elements of the real vectors x and y. For i = 1,2,...,n ( c(i) s(i) ) ( x(i) ) = ( a(i) ) ( -s(i) c(i) ) ( y(i) ) = ( 0 ) ParametersN N is INTEGER The number of plane rotations to be generated. X X is DOUBLE PRECISION array, dimension (1+(N-1)*INCX) On entry, the vector x. On exit, x(i) is overwritten by a(i), for i = 1,...,n. INCX INCX is INTEGER The increment between elements of X. INCX > 0. Y Y is DOUBLE PRECISION array, dimension (1+(N-1)*INCY) On entry, the vector y. On exit, the sines of the plane rotations. INCY INCY is INTEGER The increment between elements of Y. INCY > 0. C C is DOUBLE PRECISION array, dimension (1+(N-1)*INCC) The cosines of the plane rotations. INCC INCC is INTEGER The increment between elements of C. INCC > 0. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutineslargv(integern,real,dimension(*)x,integerincx,real,dimension(*)y,integerincy,real,dimension(*)c,integerincc)SLARGV generates a vector of plane rotations with real cosines and real sines. Purpose: SLARGV generates a vector of real plane rotations, determined by elements of the real vectors x and y. For i = 1,2,...,n ( c(i) s(i) ) ( x(i) ) = ( a(i) ) ( -s(i) c(i) ) ( y(i) ) = ( 0 ) ParametersN N is INTEGER The number of plane rotations to be generated. X X is REAL array, dimension (1+(N-1)*INCX) On entry, the vector x. On exit, x(i) is overwritten by a(i), for i = 1,...,n. INCX INCX is INTEGER The increment between elements of X. INCX > 0. Y Y is REAL array, dimension (1+(N-1)*INCY) On entry, the vector y. On exit, the sines of the plane rotations. INCY INCY is INTEGER The increment between elements of Y. INCY > 0. C C is REAL array, dimension (1+(N-1)*INCC) The cosines of the plane rotations. INCC INCC is INTEGER The increment between elements of C. INCC > 0. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. subroutinezlargv(integern,complex*16,dimension(*)x,integerincx,complex*16,dimension(*)y,integerincy,doubleprecision,dimension(*)c,integerincc)ZLARGV generates a vector of plane rotations with real cosines and complex sines. Purpose: ZLARGV generates a vector of complex plane rotations with real cosines, determined by elements of the complex vectors x and y. For i = 1,2,...,n ( c(i) s(i) ) ( x(i) ) = ( r(i) ) ( -conjg(s(i)) c(i) ) ( y(i) ) = ( 0 ) where c(i)**2 + ABS(s(i))**2 = 1 The following conventions are used (these are the same as in ZLARTG, but differ from the BLAS1 routine ZROTG): If y(i)=0, then c(i)=1 and s(i)=0. If x(i)=0, then c(i)=0 and s(i) is chosen so that r(i) is real. ParametersN N is INTEGER The number of plane rotations to be generated. X X is COMPLEX*16 array, dimension (1+(N-1)*INCX) On entry, the vector x. On exit, x(i) is overwritten by r(i), for i = 1,...,n. INCX INCX is INTEGER The increment between elements of X. INCX > 0. Y Y is COMPLEX*16 array, dimension (1+(N-1)*INCY) On entry, the vector y. On exit, the sines of the plane rotations. INCY INCY is INTEGER The increment between elements of Y. INCY > 0. C C is DOUBLE PRECISION array, dimension (1+(N-1)*INCC) The cosines of the plane rotations. INCC INCC is INTEGER The increment between elements of C. INCC > 0. Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. FurtherDetails: 6-6-96 - Modified with a new algorithm by W. Kahan and J. Demmel This version has a few statements commented out for thread safety (machine parameters are computed on each entry). 10 feb 03, SJH.

largv - largv: generate vector of plane rotations

Functions subroutine clargv (n, x, incx, y, incy, c, incc) CLARGV generates a vector of plane rotations with real cosines and complex sines. subroutine dlargv (n, x, incx, y, incy, c, incc) DLARGV generates a vector of plane rotations with real cosines and real sines. subroutine slargv (n, x, incx, y, incy, c, incc) SLARGV generates a vector of plane rotations with real cosines and real sines. subroutine zlargv (n, x, incx, y, incy, c, incc) ZLARGV generates a vector of plane rotations with real cosines and complex sines.