Ln

Declaration:

Function Ln (X : real) : Real;

Description:

Ln returns the natural logarithm of the real parameter X. X must be positive.

Errors:

An run-time error will occur when X is negative.

See also:

Exp, Power

Example

Program Example37;

{ Program to demonstrate the Ln function. }

begin
  Writeln (Ln(1));      { Prints 0 }
  Writeln (Ln(Exp(1))); { Prints 1 }
end.