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# `log10', `log10f'--base 10 logarithms

*Synopsis*
#include <math.h>
double log10(double X);
float log10f(float X);
*Description*
`log10' returns the base 10 logarithm of X. It is implemented as
`log(X) / log(10)'.

`log10f' is identical, save that it takes and returns `float' values.

*Returns*
`log10' and `log10f' return the calculated value.

See the description of `log' for information on errors.

*Portability*
`log10' is ANSI C. `log10f' is an extension.

Created Mon Nov 8 17:42:56 2004 on tillpc with info_to_html version 0.9.6.