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C library function - log()
Description
The C library function double log(double x) returns the natural logarithm (base-e logarithm) of x.
Declaration
Following is the declaration for log() function.
double log(double x)
Parameters
x − This is the floating point value.
Return Value
This function returns natural logarithm of x.
Example
The following example shows the usage of log() function.
#include <stdio.h> #include <math.h> int main () { double x, ret; x = 2.7; /* finding log(2.7) */ ret = log(x); printf("log(%lf) = %lf", x, ret); return(0); }
Let us compile and run the above program that will produce the following result −
log(2.700000) = 0.993252
math_h.htm
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