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<H2><A NAME="7_11">7.11 Adjusting labels on a text scale</A></H2>
<P> In the following section we will work through an number of examples
 on how to manipulate labels on a text scale. Primarily we will
 investigate how to best handle the case where you have a large number
 of values.</P>
<P> As a remainder; Text scale is meant to be used on the X-axis when
 the X-axis doesn't have a numeric value, i.e you are only interested in
 linear ordering of the data. If you don't specify the labels manually
 they will be set automatically starting from 1 as the example below
 shows.</P>
<P><DIV class="example">
<BR> <A href="exframes/frame_bartutex1.html" target="blank"><IMG border="0"
HEIGHT="200"       src="img/img/img/img/img/img/bartutex1.png" WIDTH="300"></A>
<BR><B>Figure 83:</B> A simple bar plot using an automatic text scale <A href="exframes/frame_bartutex1.html"
target="blank">[src]</A>&nbsp;
<P></P>
</DIV></P>
<P></P>
<P> To specify the labels on the X-axis as suitable text strings you
 call the method <A href="../ref/Axis.html#_AXIS_SETTICKLABELS">
 Axis::SetTickLabels()</A> with an array containing the text-labels. If
 there are more data points than labels the non-specified labels will be
 given their ordinal number. If we augment the previous example with the
 name of the month we get the following new example</P>
<P><DIV class="example">
<BR> <A href="exframes/frame_bartutex2.html" target="blank"><IMG border="0"
HEIGHT="200"       src="img/img/img/img/img/img/bartutex2.png" WIDTH="300"></A>
<BR><B>Figure 84:</B> Manually specifying the text scale labels <A href="exframes/frame_bartutex2.html"
target="blank">[src]</A>&nbsp;
<P></P>
</DIV></P>
<P></P>
<P></P>
<HR> <SMALL><STRONG> Tip:</STRONG> To get hold of localized version of
 the month names (or weekdays) you can use the <A href="../ref/DateLocale.html#_C_DATELOCALE">
 DateLocal</A> class available in the global variable $gDateLocale If no
 locale has been specified the default locale for the installation will
 be used.</SMALL>
<HR>
<P> What happen now if we have a larger number of bars? Let's try with
 25 bars and see what result we get.</P>
<P><DIV class="example">
<BR> <A href="exframes/frame_bartutex3.html" target="blank"><IMG border="0"
HEIGHT="200"       src="img/img/img/img/img/img/bartutex3.png" WIDTH="300"></A>
<BR><B>Figure 85:</B> A larger data set <A href="exframes/frame_bartutex3.html"
target="blank">[src]</A>&nbsp;
<P></P>
</DIV></P>
<P></P>
<P> Not all to impressive. The labels are to close and they overlap.
 Hence it is not a good idea to display every label. To adjust what
 labels are to be displayed you use the <A href="../ref/Axis.html#_AXIS_SETTEXTLABELINTERVAL">
 SetTextLabelInterval()</A> method. The argument to this method is the
 interval between text labels. So to display only every 3 month you
 would add the line</P>
<P><DIV class="phpscript"><CODE><FONT color="#000000"> <FONT color="#0000BB">
&nbsp;$graph</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">xaxis</FONT><FONT
color="#007700">-&gt;</FONT><FONT color="#0000BB">SetTextLabelIntervall</FONT><FONT
color="#007700">(</FONT><FONT color="#0000BB">3</FONT><FONT color="#007700">
)</FONT><FONT color="#0000BB"></FONT></FONT></CODE></DIV></P>
<P></P>
<P> Which would give the result shown below<DIV class="example">
<BR> <A href="exframes/frame_bartutex4.html" target="blank"><IMG border="0"
HEIGHT="200"       src="img/img/img/img/img/img/bartutex4.png" WIDTH="300"></A>
<BR><B>Figure 86:</B> Displaying only every third label <A href="exframes/frame_bartutex4.html"
target="blank">[src]</A>&nbsp;
<P></P>
</DIV></P>
<P></P>
<P> Much better, quite readable.</P>
<P> If we have an even larger data set it might not longer be meaningful
 to display all the tick marks since they would simple become to close.
 In JpGraph there is a possibility to specify that you only would like
 every<I> n</I>:th tick mark to be visible ( <A href="../ref/Axis.html#_AXIS_SETTEXTTICKINTERVAL">
 SetTextTickIntervall()</A> ). For bar graphs using text scale however,
 that might not be such a good idea since the tick marks are between the
 bars and the labels centered under the bars. If we only were to
 display, say, every 3 tick mark it wouldn't look to good. Not that we
 can't do it, as the example below shows, but it just doesn't look very
 good.<DIV class="example">
<BR> <A href="exframes/frame_bartutex5.html" target="blank"><IMG border="0"
HEIGHT="200"       src="img/img/img/img/img/img/bartutex5.png" WIDTH="300"></A>
<BR><B>Figure 87:</B> Displaying just every third tick mark. <A href="exframes/frame_bartutex5.html"
target="blank">[src]</A>&nbsp;
<P></P>
</DIV></P>
<P></P>
<P> A better way to handle large data set is simply to hide the tick
 marks all together. Tick marks may be hidden by calling the method <A href="../ref/Axis.html#_AXIS_HIDETICKS">
 Axis::HideTicks(); <A> If we hide all the ticks on the X-axis we will
 get the result shown below<DIV class="example">
<BR> <A href="exframes/frame_bartutex6.html" target="blank"><IMG border="0"
HEIGHT="200"       src="img/img/img/img/img/img/bartutex6.png" WIDTH="300"></A>
<BR><B>Figure 88:</B> Hiding all tick mark. <A href="exframes/frame_bartutex6.html"
target="blank">[src]</A>&nbsp;
<P></P>
</DIV></A></A></P>
<P></P>
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