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cephes
cephes
tandg.c
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/* tandg.c
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*
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* Circular tangent of argument in degrees
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*
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*
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*
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* SYNOPSIS:
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*
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* double x, y, tandg();
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*
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* y = tandg( x );
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*
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*
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*
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* DESCRIPTION:
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*
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* Returns the circular tangent of the argument x in degrees.
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*
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* Range reduction is modulo pi/4. A rational function
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* x + x**3 P(x**2)/Q(x**2)
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* is employed in the basic interval [0, pi/4].
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*
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*
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*
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* ACCURACY:
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*
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* Relative error:
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* arithmetic domain # trials peak rms
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* IEEE 0,10 30000 3.2e-16 8.4e-17
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*
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* ERROR MESSAGES:
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*
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* message condition value returned
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* tandg total loss x > 1.0e14 (IEEE) 0.0
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* tandg singularity x = 180 k + 90 INFINITY
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*/
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/* cotdg.c
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*
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* Circular cotangent of argument in degrees
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*
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*
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*
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* SYNOPSIS:
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*
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* double x, y, cotdg();
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*
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* y = cotdg( x );
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*
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*
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*
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* DESCRIPTION:
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*
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* Returns the circular cotangent of the argument x in degrees.
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*
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* Range reduction is modulo pi/4. A rational function
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* x + x**3 P(x**2)/Q(x**2)
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* is employed in the basic interval [0, pi/4].
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*
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*
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* ERROR MESSAGES:
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*
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* message condition value returned
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* cotdg total loss x > 1.0e14 (IEEE) 0.0
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* cotdg singularity x = 180 k INFINITY
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*/
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/*
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* Cephes Math Library Release 2.0: April, 1987
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* Copyright 1984, 1987 by Stephen L. Moshier
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* Direct inquiries to 30 Frost Street, Cambridge, MA 02140
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*/
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#include "
mconf.h
"
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static
double
PI180
= 1.74532925199432957692E-2;
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static
double
lossth
= 1.0e14;
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static
double
tancot
(
double
,
int
);
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double
tandg
(
double
x
)
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{
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return
(
tancot
(
x
, 0));
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}
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double
cotdg
(
double
x
)
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{
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return
(
tancot
(
x
, 1));
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}
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static
double
tancot
(
double
xx,
int
cotflg)
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{
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double
x
;
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int
sign
;
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/* make argument positive but save the sign */
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if
(xx < 0) {
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x
= -xx;
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sign
= -1;
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}
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else
{
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x
= xx;
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sign
= 1;
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}
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if
(
x
>
lossth
) {
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sf_error
(
"tandg"
,
SF_ERROR_NO_RESULT
,
NULL
);
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return
0.0;
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}
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/* modulo 180 */
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x
=
x
- 180.0 *
floor
(
x
/ 180.0);
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if
(cotflg) {
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if
(
x
<= 90.0) {
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x
= 90.0 -
x
;
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}
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else
{
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x
=
x
- 90.0;
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sign
*= -1;
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}
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}
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else
{
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if
(
x
> 90.0) {
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x
= 180.0 -
x
;
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sign
*= -1;
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}
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}
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if
(
x
== 0.0) {
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return
0.0;
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}
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else
if
(
x
== 45.0) {
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return
sign
* 1.0;
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}
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else
if
(
x
== 90.0) {
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sf_error
((cotflg ?
"cotdg"
:
"tandg"
),
SF_ERROR_SINGULAR
,
NULL
);
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return
INFINITY;
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}
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/* x is now transformed into [0, 90) */
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return
sign
*
tan
(
x
*
PI180
);
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}
SF_ERROR_NO_RESULT
@ SF_ERROR_NO_RESULT
Definition:
sf_error.h:15
x
set noclip points set clip one set noclip two set bar set border lt lw set xdata set ydata set zdata set x2data set y2data set boxwidth set dummy x
Definition:
gnuplot_common_settings.hh:12
PI180
static double PI180
Definition:
tandg.c:75
sign
const EIGEN_DEVICE_FUNC SignReturnType sign() const
Definition:
ArrayCwiseUnaryOps.h:219
tancot
static double tancot(double, int)
Definition:
tandg.c:92
cotdg
double cotdg(double x)
Definition:
tandg.c:86
tan
const EIGEN_DEVICE_FUNC TanReturnType tan() const
Definition:
ArrayCwiseUnaryOps.h:269
lossth
static double lossth
Definition:
tandg.c:76
mconf.h
sf_error
void sf_error(const char *func_name, sf_error_t code, const char *fmt,...)
Definition:
sf_error.c:41
SF_ERROR_SINGULAR
@ SF_ERROR_SINGULAR
Definition:
sf_error.h:10
tandg
double tandg(double x)
Definition:
tandg.c:80
NULL
#define NULL
Definition:
ccolamd.c:609
floor
const EIGEN_DEVICE_FUNC FloorReturnType floor() const
Definition:
ArrayCwiseUnaryOps.h:481
gtsam
Author(s):
autogenerated on Sat Nov 16 2024 04:05:22