std::log10(std::complex)

 

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std::complex

成员函数
complex::complex complex::operator= complex::real complex::imag	complex::operator+=complex::operator-=complex::operator*=complex::operator/=
非成员函数
operator+operator- operator+operator-operator*operator/ operator==operator!= (C++20 前)   operator<<operator>> get(std::complex) (C++26)	real imag abs arg norm conj proj (C++11) polar operator""ioperator""ifoperator""il (C++14)(C++14)(C++14)
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log   log10   exp
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pow   sqrt
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sin   cos tan asin (C++11) acos (C++11) atan (C++11)
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sinh   cosh tanh asinh (C++11) acosh (C++11) atanh (C++11)
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tuple_size<std::complex> (C++26)
tuple_element<std::complex> (C++26)

 

在标头 <complex> 定义
template< class T > std::complex<T> log10( const std::complex<T>& z );

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

log(std::complex)	沿负实轴切割的复自然对数 (函数模板)
log10log10flog10l (C++11)(C++11)	计算常用（以 10 为底）对数（\({\small \log_{10}{x} }\)log10(x)） (函数)
log10(std::valarray)	应用函数 std::log10 到 valarray 的每个元素 (函数模板)