c语言atof函数
C ++ atof()函数 (C++ atof() function)atof() function is a library function of cstdlib header. It is used to convert the given string value to the double value. It accepts a string containing a floating-point number and returns its double value.
atof()函数是cstdlib标头的库函数。 它用于将给定的字符串值转换为双精度值。 它接受包含浮点数的字符串，并返回其双精度值。
Syntax of atof() function:
atof()函数的语法：
C++11:
C ++ 11：
double atof (const char* str);Parameter(s):
参数：
str – represents a string containing a floating-point number.
str –表示包含浮点数的字符串。
Return value:
返回值：
The return type of this function is double, it returns the double converted value.
该函数的返回类型为double ，它返回double转换后的值。
Example:
例：
Input: str = "123.456"; Function call: atof(str); Output: 123.456 C ++代码演示atof()函数的示例 (C++ code to demonstrate the example of atof() function) // C++ code to demonstrate the example of// atof() function#include <iostream>#include <cstdlib>#include <string.h>using namespace std;// main() sectionint main(){ char str[50]; strcpy(str, "123.456"); cout << "atof("" << str << ""): " << atof(str) << endl; strcpy(str, "-123.456"); cout << "atof("" << str << ""): " << atof(str) << endl; strcpy(str, "0.123456"); cout << "atof("" << str << ""): " << atof(str) << endl; strcpy(str, "-0.123456"); cout << "atof("" << str << ""): " << atof(str) << endl; strcpy(str, "12345678.123456"); cout << "atof("" << str << ""): " << atof(str) << endl; strcpy(str, "-12345678.123456"); cout << "atof("" << str << ""): " << atof(str) << endl; return 0;}Output
输出量
atof("123.456"): 123.456atof("-123.456"): -123.456atof("0.123456"): 0.123456atof("-0.123456"): -0.123456atof("12345678.123456"): 1.23457e+07atof("-12345678.123456"): -1.23457e+07Reference: C++ atof() function
参考： C ++ atof()函数
翻译自: https://www.includehelp.com/cpp-tutorial/atof-function-with-example.aspx
c语言atof函数