std::log10(std::complex)

来自cppreference.com
 
C++
 
数值库
 
std::complex
 
<tbody> </tbody>
在标头 <complex> 定义
template< class T > std::complex<T> log10( const std::complex<T>& z );
See More

计算复数值 z 的复常用（底 10）对数，分支切割线沿负实轴。

此函数的行为等价于 std::log(z) / std::log(T(10))。

参数

z - 复数值

返回值

z 的复常用对数

示例

运行此代码
#include <cmath>
#include <complex>
#include <iostream>

int main()
{
    std::complex<double> z(0.0, 1.0); // r = 0, θ = pi / 2
    std::cout << "2 * log10" << z << " = " << 2.0 * std::log10(z) << '\n';

    std::complex<double> z2(sqrt(2.0) / 2, sqrt(2.0) / 2); // r = 1, θ = pi / 4
    std::cout << "4 * log10" << z2 << " = " << 4.0 * std::log10(z2) << '\n';

    std::complex<double> z3(-100.0, 0.0); // r = 100, θ = pi
    std::cout << "log10" << z3 << " = " << std::log10(z3) << '\n';
    std::complex<double> z4(-100.0, -0.0); // 切割的另一侧
    std::cout << "log10" << z4 << " = " << std::log10(z4) << " "
                 "(the other side of the cut)\n"
                 "(note: pi / log(10) = " << std::acos(-1.0) / std::log(10.0) << ")\n";
}

可能的输出： 

2 * log10(0,1) = (0,1.36438)
4 * log10(0.707107,0.707107) = (0,1.36438)
log10(-100,0) = (2,1.36438)
log10(-100,-0) = (2,-1.36438) (the other side of the cut)
(note: pi / log(10) = 1.36438)

参阅

 沿负实轴切割的复自然对数
(函数模板) [编辑]
(C++11)(C++11)
 计算常用（以 10 为底）对数（log10(x)）
(函数) [编辑]
应用函数 std::log10 到 valarray 的每个元素
(函数模板) [编辑]