complex.3

speech signal process tools

.\" Copyright (c) 1987, 1990 Entropic Speech, Inc.; All rights reserved
.\" @(#)complex.3	1.5 19 Mar 1990 ESI
.TH COMPLEX 3\-ESPSsp 19 Mar 1990
.ds ]W "\fI\s+4\ze\h'0.05'e\s-4\v'-0.4m'\fP\(*p\v'0.4m'\ Entropic Speech, Inc.
.SH NAME
.nf
cadd \- returns the complex sum of two complex numbers
csub \- returns the complex difference of two complex numbers
cmult \- returns the complex product of two complex numbers
cdiv \- returns the complex division of two complex numbers
conj \- returns the complex conjugate of its argument
realmult \- returns the complex product of a real and a complex number
realadd \- returns the complex result of adding a real and a complex
cmultacc \- returns the product of two complex numbers added to a third
modul \- returns the absolute value of a complex number
csqrt \- returns the square root (positive real if possible) of a complex number
.SH SYNOPSIS
.ft B
typedef struct  {
.br
	double real;
.br
	double imag;
.br
} double_cplx;
.sp
.PP
.ft B
# include <esps/esps.h>
.sp
.PP
.ft B
double_cplx cadd (x, y)
.br
double_cplx x, y;
.PP
.ft B
double_cplx csub (x, y)
.br
double_cplx x, y;
.PP
.ft B
double_cplx cmult (x, y)
.br
double_cplx x, y;
.PP
.ft B
double_cplx cdiv (x, y)
.br
double_cplx x, y;
.PP
.ft B
double_cplx conj (x)
.br
double_cplx x;
.PP
.ft B
double_cplx realmult (x, r)
.br
double r;
.br
double_cplx x;
.PP
.ft B
double_cplx realadd (x, r)
.br
double r;
.br
double_cplx x;
.PP
.ft B
double_cplx cmultacc (x, y, z)
.br
double_cplx x, y, z;
.PP
.ft B
double modul (x)
.br
double_cplx x;
.PP
.ft B
double_cplx csqrt(x)
.br
double_cplx x;
.SH DESCRIPTION
.PP
Each function operates on one or more complex numbers. The typedef
double_cplx is defined by the inclusion of \fI<esps/esps.h>\fR,
and it is shown above for reference.  The typedef COMPLEX was used in 
previous versions of ESPS, and is defined and for convenience is now 
defined as a synonym for double_cplx.  
.sp
.PP
.I cadd 
adds two complex numbers and returns their sum.
.sp
.PP
.I csub
subtracts \fIy\fR from \fIx\fR and returns the difference.
.sp
.PP
.I cmult
multiplies \fIx\fR by \fIy\fR and returns the product.
.sp
.PP
.I cdiv
divides \fIx\fR by \fIy\fR and returns the quotient.
.sp
.PP
.I conj
returns the complex conjugate of \fIx\fR.
.sp
.PP
.I realmult
multiplies the complex number \fIx\fR by the real number \fIy\fR
and returns the product.
.sp
.PP
.I realadd
addes the complex number \fIx\fP to the real number \fIr\fP
and returns the sum.
.sp
.PP
.I cmultacc
multiplies \fIx\fR by \fIy\fR, adds it to \fIz\fR, and returns
the sum.
.sp
.PP
.I modul
returns the absolute value, or modulus, of \fIx\fR.
.sp
.PP
.I csqrt
returns the square root of \fIx\fR.
.SH DIAGNOSTICS
.PP
.I cdiv
warns and exits if the divisor is zero.
.SH AUTHOR
Code by B. F. Frankel; ESPS modification, sqrt, and realadd by D. Burton;
manual page by D. Burton.