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   catanl    ( 3 )

сложные арктангенсы (complex arc tangents)

Имя (Name)

catan, catanf, catanl - complex arc tangents


Синопсис (Synopsis)

#include <complex.h>

double complex catan(double complex z); float complex catanf(float complex z); long double complex catanl(long double complex z);

Link with -lm.


Описание (Description)

These functions calculate the complex arc tangent of z. If y = catan(z), then z = ctan(y). The real part of y is chosen in the interval [-pi/2,pi/2].

One has:

catan(z) = (clog(1 + i * z) - clog(1 - i * z)) / (2 * i)


Версии (Versions)

These functions first appeared in glibc in version 2.1.


Атрибуты (Attributes)

For an explanation of the terms used in this section, see attributes(7).

┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface Attribute Value │ ├──────────────────────────────────────┼───────────────┼─────────┤ │catan(), catanf(), catanl() │ Thread safety │ MT-Safe │ └──────────────────────────────────────┴───────────────┴─────────┘


Стандарты (Conforming to)

C99, POSIX.1-2001, POSIX.1-2008.


Примеры (Examples)

/* Link with "-lm" */

#include <complex.h> #include <stdlib.h> #include <unistd.h> #include <stdio.h>

int main(int argc, char *argv[]) { double complex z, c, f; double complex i = I;

if (argc != 3) { fprintf(stderr, "Usage: %s <real> <imag>\n", argv[0]); exit(EXIT_FAILURE); }

z = atof(argv[1]) + atof(argv[2]) * I;

c = catan(z); printf("catan() = %6.3f %6.3f*i\n", creal(c), cimag(c));

f = (clog(1 + i * z) - clog(1 - i * z)) / (2 * i); printf("formula = %6.3f %6.3f*i\n", creal(f2), cimag(f2));

exit(EXIT_SUCCESS); }


Смотри также (See also)

ccos(3), clog(3), ctan(3), complex(7)