catan
计算复数x的反正切值。
接口定义
C interface：
float complex catanf(float complex x);
double complex catan(double complex x);
long double complex catanl(long double complex x);
参数
参数名 |
类型 |
描述 |
输入/输出 |
|---|---|---|---|
x |
|
表示输入数据的浮点值。 |
输入 |
返回值
- 返回x的反正切结果y。
- 特殊值说明如下所示。
输入值实部（x.real）
输入值虚部（x.imag）
输出值实部（y.real）
输出值虚部（y.imag）
-inf
-inf
-pi/2
-0.0
-inf
< +0.0
-pi/2
-0.0
-inf
-0.0
-pi/2
-0.0
-inf
+0.0
-pi/2
+0.0
-inf
> +0.0
-pi/2
+0.0
-inf
inf
-pi/2
+0.0
-inf
-nan
-pi/2
+0.0
-inf
nan
-pi/2
+0.0
< +0.0
-inf
-pi/2
-0.0
< +0.0
inf
-pi/2
+0.0
< +0.0
-nan
nan
nan
< +0.0
nan
nan
nan
-0.0
-inf
-pi/2
-0.0
-0.0
-0.0
-0.0
-0.0
-0.0
+0.0
-0.0
0.0
-0.0
inf
-pi/2
+0.0
-0.0
-nan
nan
nan
-0.0
nan
nan
nan
+0.0
-inf
pi/2
-0.0
+0.0
-0.0
+0.0
-0.0
+0.0
+0.0
+0.0
+0.0
+0.0
inf
pi/2
+0.0
+0.0
-nan
nan
nan
+0.0
nan
nan
nan
> +0.0
-inf
pi/2
-0.0
> +0.0
inf
pi/2
+0.0
> +0.0
-nan
nan
nan
> +0.0
nan
nan
nan
inf
-inf
pi/2
-0.0
inf
< +0.0
pi/2
-0.0
inf
-0.0
pi/2
-0.0
inf
+0.0
pi/2
+0.0
inf
> +0.0
pi/2
+0.0
inf
inf
pi/2
+0.0
inf
-nan
pi/2
+0.0
inf
nan
pi/2
+0.0
-nan
-inf
nan
-0.0
-nan
< +0.0
nan
nan
-nan
-0.0
nan
-0.0
-nan
+0.0
nan
+0.0
-nan
> +0.0
nan
nan
-nan
inf
nan
+0.0
-nan
-nan
nan
nan
-nan
nan
nan
nan
nan
-inf
nan
-0.0
nan
< +0.0
nan
nan
nan
-0.0
nan
-0.0
nan
+0.0
nan
+0.0
nan
> +0.0
nan
nan
nan
inf
nan
+0.0
nan
-nan
nan
nan
nan
nan
nan
nan
依赖
C: "km.h"
示例
// typical usage
double x1 = 1.0, x2 = 2.0, x3 = 3.0, x4 = 4.0;
double complex cx1 = __builtin_complex(x1, x2);
double complex cx2 = __builtin_complex(x3, x4);
double complex cx3 = __builtin_complex(NAN, NAN);
double complex cx4 = __builtin_complex(INFINITY, -INFINITY);
double ry;
double iy;
ry = __real__ catan(cx1);
iy = __imag__ catan(cx1);
printf("catan(cx1) = %.15f, %.15f\n", ry, iy);
ry = __real__ catan(cx2);
iy = __imag__ catan(cx2);
printf("catan(cx2) = %.15f, %.15f\n", ry, iy);
ry = __real__ catan(cx3);
iy = __imag__ catan(cx3);
printf("catan(cx3) = %.15f, %.15f\n", ry, iy);
ry = __real__ catan(cx4);
iy = __imag__ catan(cx4);
printf("catan(cx4) = %.15f, %.15f\n", ry, iy);
result:
/*
* catan(cx1) = 1.338972522294493, 0.402359478108525
* catan(cx2) = 1.448306995231464, 0.158997191679999
* catan(cx3) = nan, nan
* catan(cx4) = 1.570796326794897, -0.000000000000000
*/
