CIGAL Reference Manual, Chapter 0 (log):

Log -- Calculate the logarithm of a variable

usage: result = log(x)

The LOG function returns the logarithm of its argument (base 10). If the input value is too large (>= 13) the routine returns 0. If the input X is a variable with more than one value, LOG will generate an output variable of logarithms with the same number of values.

See Also:
ALOG(3)

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