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## log function - find logarithm

You can use the ** log ** function to find the natural logarithm. You can also use the base transformation to calculate the logarithm of any base.

#### Find the natural logarithm

Use the log function to find the natural logarithm. The natural logarithm is the logarithm whose base is the Napier number e.

log(10);

#### Find the common logarithm

The common logarithm is a logarithm with a base of 10. You can use the logarithms change formula to find the logarithm of any base.

sub log10 { my $x = shift; return log($x)/log(10); }

### Example program

This is an example to find the logarithm using the log function.

use strict; use warnings; # The base of the logarithm is the Napier number e; print "(1) Natural logarithm\n"; print "log(3) =" . Log (10). "\n\n"; print "(2) Common logarithm\n"; print "log10 (100) =" . Log10 (100) . "\n"; # A function to find the logarithm with a base of 10 (using the logarithms of the base) sub log10 { my $x = shift; return log($x)/log(10); }