LOG - mkilgore/QB64pe GitHub Wiki

The LOG math function returns the natural logarithm of a specified numerical value.

logarithm! = LOG(value)

• value MUST be greater than 0. "Illegal function call" error occurs if negative or zero values are used.
• The natural logarithm is the logarithm to the base e = 2.718282 (approximately).
• The natural logarithm of a is defined as the integral from 1 to a of dx/x.
• Returns are default SINGLE precision unless the value parameter uses DOUBLE precision.

Example 1: FUNCTION to find the base ten logarithm of a numerical value.

 FUNCTION Log10#(value AS DOUBLE) STATIC
   Log10# = LOG(value) / LOG(10.#) 
 END FUNCTION '' ''

Explanation: The natural logarithm of the value is divided by the base 10 logarithm. The LOG of ten is designated as a DOUBLE precision return by using # after the Log10 value. The return tells you the number of times 10 goes into a value.

Explanation: The LOG of a positive INTEGER value is divided by the LOG of 2 to determine the number of binary digits that will be returned. The FOR loop compares the value with the exponents of two and determines if a bit is ON or OFF as "1" or "0".

• EXP, &B (binary number)
• Derived Trigonometric Functions