fabs is a C language library function used to calculate the absolute value of floating point numbers, that is, regardless of sign. Its prototype is double fabs(double x), the parameter x is the target floating point number, and the return value is its absolute value, which is a non-negative double type.
What are fabs?
fabs is a library function in C language that is used to calculate the absolute value of floating point numbers, that is, regardless of sign.
fabs Function prototype:
double fabs(double x);
Function parameters:
-
x
: Required Calculate the target floating point number of the absolute value
Return value:
fabs function returns the absolute value of x, which is a non-negative double type value.
Usage of fabs function:
The following is an example of how to use the fabs function in a C program:
#include <stdio.h> #include <math.h> int main() { // 计算 -5.5 的绝对值 double absolute_value = fabs(-5.5); // 打印绝对值 printf("绝对值:%.2f\n", absolute_value); return 0; }
Output:
<code>绝对值:5.50</code>
Note:
- fabs function can only handle floating point numbers, not integers.
- If you want to calculate the absolute value of an integer, you can use the
abs()
function.
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