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5.1.2 Logarithmic projection

Figure 5.2: Logarithmic transformation of $x$-coordinates
\begin{figure}\centering\epsfig{figure=eps/GMT_log.eps}\end{figure}

The log$_{10}$ transformation is selected by appending an l (lower case L) immediately following the scale (or axis length) value. Hence, to produce a plot in which the x-axis is logarithmic (the y-axis remains linear), try





#!/bin/sh
#    $Id: GMT_log.sh,v 1.1 2001/03/21 04:10:21 pwessel Exp $
#

psxy -R1/100/0/10 -Jx1.5il/0.15i -B2g3/a2f1g2WSne -W1t2_2:0p -P -K -H sqrt.d > GMT_log.ps
psxy -R -Jx -Ss0.075i -G0 -W -O -H sqrt.d10 >> GMT_log.ps





Note that if x- and y-scaling are different and a log$_{10}$-log$_{10}$ plot is desired, the l must be appended twice: Once after the x-scale (before the /) and once after the y-scale.



Paul Wessel 2001-04-18