Great Cow BASIC support logarithmic functions through the include file <maths.h>.

These functions compute base 2, base e and base 10 logarithms accurate to 2 decimal places, +/- 0.01.

The values returned are fixed-point numbers, with two decimal places assumed on the right. Or if you prefer, think of the values as being scaled up by 100.

The input arguments are word-sized integers, 1 to 65535. Remember, logarithms are not defined for non-positive numbers. It is the calling program’s responsibility to avoid these. Output values are also word-sized.

Local variables consume 9 bytes, while the function parameters consume another 4 bytes, for a grand total of 13 bytes of RAM used. The lookup table takes 35 words of program memory.

For more help, see Log10, Log2, Loge

Supported in <MATHS.H>