catanh函数用法详解

catanh函数简介

• 头文件包含

#include <complex.h>

• 函数定义

double complex catanh(double complex  z );
float complex catanhf(float complex  z );
long double complex catanhl(long double complex  z );

• 编译链接选项

-lm

catanh函数常见使用错误

• 链接错误
  undefined reference to `catanh'
  解决办法：添加链接选项

-lm

• 编译错误
  warning: implicit declaration of function ‘catanh’ [-Wimplicit-function-declaration]
  解决办法：包含头文件

#include <complex.h>

catanh函数详细描述

这些函数计算z 的复圆弧双曲切线，如果y = catanh(z)，然后pz = ctanh(y)。在区间[\-pi/2,pi/2]中选择y的虚部。
一个有：

   catanh(z) = 0.5 * (clog(1 + z) \- clog(1 \- z))

catanh函数使用举例

/* 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;

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

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

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

   f = 0.5 * (clog(1 + z) \- clog(1 \- z));
   printf("formula  = %6.3f %6.3f*i\en", creal(f2), cimag(f2));

   exit(EXIT_SUCCESS);
}