log()

Synopsis

float log(float x);

Parameters

Return value

In the event of an error, the function returns 0.0.

If the argument is lying outside of the value range ]0..], NaN (Not a Number) is returned.

Description

Returns the natural logarithm (base e) of x, for x > 0.

Example

main()
{
  float f;
  f = log(1);
// returns 0
  f = log(100);
// returns 4.6051701859881
  f = exp(log(10));
// returns 10
}

Assignment

mathematical function

Availability

CTRL