catan(3)                   Library Functions Manual                   catan(3)

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       catan, catanf, catanl - <?><?> <?><?><?><?> <?><?><?><?>

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       <?><?><?><?><?> <?><?><?><?><?><?><?><?><?> (libm<?> -lm)

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       #include <complex.h>

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

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       <?><?><?><?><?><?> <?><?><?><?><?><?> <?><?> z. <?><?><?> <?><?><?>
       y = catan(z)<?> <?><?><?> z = ctan(y). <?><?><?><?><?><?>
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       <?><?><?><?><?><?> [-pi/2, pi/2].

       <?><?><?><?><?>:

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

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       <?><?><?><?> attributes(7).

       +------------+------------------------------------+--------------------+
       |<?><?><?><?><?><?><?>|<?><?><?><?><?>            | <?><?><?><?><?><?> |
       +------------+------------------------------------+--------------------+
       |catan(),    | <?><?><?><?><?> <?><?><?><?><?><?> | MT-Safe            |
       |catanf(),   |                                    |                    |
       |catanl()    |                                    |                    |
       +------------+------------------------------------+--------------------+
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       C11, POSIX.1-2008.

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       glibc 2.1.  C99<?> POSIX.1-2001.

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       /* Link with "-lm" */

       #include <complex.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <unistd.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(f), cimag(f));

           exit(EXIT_SUCCESS);
       }

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

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       <?><?><?><?><?><?><?> <zayed.alsaidi@gmail.com>

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       <kde-l10n-ar@kde.org>.


<?><?><?><?><?> <?><?><?><?> <?><?><?><?><?> 6.18
                           8 <?><?><?><?><?><?> 2026                  catan(3)