<!--Copyright (C) 1988-2005 by the Institute of Global Environment and Society (IGES). See file COPYRIGHT for more information.--> <h2><b>log10</b></h2><p> <code>log10(<i>expr</i>) </code><p> Takes the logarithm base 10 of the expression. May be used with gridded or station data. Values less than or equal to zero are set to missing in the result. <H3>Usage Notes</H3><P> <H3>Examples</H3><P>