ccnvcor(3P) Sun Performance Library ccnvcor(3P)NAMEccnvcor - compute the convolution or correlation of complex vectors
SYNOPSIS
SUBROUTINE CCNVCOR(CNVCOR, FOUR, NX, X, IFX, INCX, NY, NPRE, M, Y,
IFY, INC1Y, INC2Y, NZ, K, Z, IFZ, INC1Z, INC2Z, WORK, LWORK)
CHARACTER * 1 CNVCOR, FOUR
COMPLEX X(*), Y(*), Z(*), WORK(*)
INTEGER NX, IFX, INCX, NY, NPRE, M, IFY, INC1Y, INC2Y, NZ, K, IFZ,
INC1Z, INC2Z, LWORK
SUBROUTINE CCNVCOR_64(CNVCOR, FOUR, NX, X, IFX, INCX, NY, NPRE, M, Y,
IFY, INC1Y, INC2Y, NZ, K, Z, IFZ, INC1Z, INC2Z, WORK, LWORK)
CHARACTER * 1 CNVCOR, FOUR
COMPLEX X(*), Y(*), Z(*), WORK(*)
INTEGER*8 NX, IFX, INCX, NY, NPRE, M, IFY, INC1Y, INC2Y, NZ, K, IFZ,
INC1Z, INC2Z, LWORK
F95 INTERFACE
SUBROUTINE CNVCOR(CNVCOR, FOUR, NX, X, IFX, [INCX], NY, NPRE, M, Y,
IFY, INC1Y, INC2Y, NZ, K, Z, IFZ, INC1Z, INC2Z, WORK, [LWORK])
CHARACTER(LEN=1) :: CNVCOR, FOUR
COMPLEX, DIMENSION(:) :: X, Y, Z, WORK
INTEGER :: NX, IFX, INCX, NY, NPRE, M, IFY, INC1Y, INC2Y, NZ, K, IFZ,
INC1Z, INC2Z, LWORK
SUBROUTINE CNVCOR_64(CNVCOR, FOUR, NX, X, IFX, [INCX], NY, NPRE, M,
Y, IFY, INC1Y, INC2Y, NZ, K, Z, IFZ, INC1Z, INC2Z, WORK, [LWORK])
CHARACTER(LEN=1) :: CNVCOR, FOUR
COMPLEX, DIMENSION(:) :: X, Y, Z, WORK
INTEGER(8) :: NX, IFX, INCX, NY, NPRE, M, IFY, INC1Y, INC2Y, NZ, K,
IFZ, INC1Z, INC2Z, LWORK
C INTERFACE
#include <sunperf.h>
void ccnvcor(char cnvcor, char four, int nx, complex *x, int ifx, int
incx, int ny, int npre, int m, complex *y, int ify, int
inc1y, int inc2y, int nz, int k, complex *z, int ifz, int
inc1z, int inc2z, complex *work, int lwork);
void ccnvcor_64(char cnvcor, char four, long nx, complex *x, long ifx,
long incx, long ny, long npre, long m, complex *y, long ify,
long inc1y, long inc2y, long nz, long k, complex *z, long
ifz, long inc1z, long inc2z, complex *work, long lwork);
PURPOSEccnvcor computes the convolution or correlation of complex vectors.
ARGUMENTS
CNVCOR (input)
CHARACTER
´V' or 'v' if convolution is desired, 'R' or 'r' if correla‐
tion is desired.
FOUR (input)
CHARACTER
´T' or 't' if the Fourier transform method is to be used, 'D'
or 'd' if the computation should be done directly from the
definition. The Fourier transform method is generally
faster, but it may introduce noticeable errors into certain
results, notably when both the real and imaginary parts of
the filter and data vectors consist entirely of integers or
vectors where elements of either the filter vector or a given
data vector differ significantly in magnitude from the 1-norm
of the vector.
NX (input)
Length of the filter vector. NX >= 0. CCNVCOR will return
immediately if NX = 0.
X (input)
dimension(*)
Filter vector.
IFX (input)
Index of the first element of X. NX >= IFX >= 1.
INCX (input)
Stride between elements of the filter vector in X. INCX > 0.
NY (input)
Length of the input vectors. NY >= 0. CCNVCOR will return
immediately if NY = 0.
NPRE (input)
The number of implicit zeros prepended to the Y vectors.
NPRE >= 0.
M (input)
Number of input vectors. M >= 0. CCNVCOR will return imme‐
diately if M = 0.
Y (input)
dimension(*)
Input vectors.
IFY (input)
Index of the first element of Y. NY >= IFY >= 1.
INC1Y (input)
Stride between elements of the input vectors in Y. INC1Y >
0.
INC2Y (input)
Stride between the input vectors in Y. INC2Y > 0.
NZ (input)
Length of the output vectors. NZ >= 0. CCNVCOR will return
immediately if NZ = 0. See the Notes section below for
information about how this argument interacts with NX and NY
to control circular versus end-off shifting.
K (input)
Number of Z vectors. K >= 0. If K = 0 then CCNVCOR will
return immediately. If K < M then only the first K input
vectors will be processed. If K > M then M input vectors
will be processed.
Z (output)
dimension(*)
Result vectors.
IFZ (input)
Index of the first element of Z. NZ >= IFZ >= 1.
INC1Z (input)
Stride between elements of the output vectors in Z. INC1Z >
0.
INC2Z (input)
Stride between the output vectors in Z. INC2Z > 0.
WORK (input/output)
(input/scratch) dimension(LWORK)
Scratch space. Before the first call to CCNVCOR with partic‐
ular values of the integer arguments the first element of
WORK must be set to zero. If WORK is written between calls
to CCNVCOR or if CCNVCOR is called with different values of
the integer arguments then the first element of WORK must
again be set to zero before each call. If WORK has not been
written and the same values of the integer arguments are used
then the first element of WORK to zero. This can avoid cer‐
tain initializations that store their results into WORK, and
avoiding the initialization can make CCNVCOR run faster.
LWORK (input)
Length of WORK. LWORK >= 2*MAX(NX,NY+NPRE,NZ)+8.
6 Mar 2009 ccnvcor(3P)
