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  28  <H2><A NAME="8_8">8.8 Specifying the scale manually</A></H2>
  29  <P> Normally the automatic scaling should be doing an adequate job in
  30   most circumstances but there might be cases where you like to manually
  31   set the scale. For example if you have several graphs where you like to
  32   be able to easily compare them and therefore want them all to have the
  33   same scale.</P>
  34  <P> To specify a manual scale you have to add arguments to the standard <A
  35  href="../ref/Graph.html#_GRAPH_SETSCALE"> Graph::SetScale()</A> method.
  36   So to specify that you want an Y-scale between 0 and 100 you need to
  37   write<DIV class="phpscript"><CODE><FONT color="#000000"> <FONT color="#0000BB">
  38  &nbsp;$graph</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">
  39  SetScale</FONT><FONT color="#007700">(</FONT><FONT color="#DD0000">
  40  &quot;textlin&quot;</FONT><FONT color="#007700">,</FONT><FONT color="#0000BB">0</FONT><FONT
  41  color="#007700">,</FONT><FONT color="#0000BB">100</FONT><FONT color="#007700">
  42  );</FONT><FONT color="#0000BB"></FONT></FONT></CODE></DIV></P>
  43  <P>When you specify a scale manually there is one additional thing you
  44   need to decide. How the tick marks should be positioned. You have three
  45   choices</P>
  46  <OL>
  47  <LI> Let JpGraph decide suitable tick marks honoring the exact scale you
  48   specified.<B> This is the default behavior</B> if you don't do anything
  49   else.</LI>
  50  <LI> Allow JpGraph to slightly adjust your specified min and max values.
  51   With the default method, depending on the min and max values, the end
  52   and start of the scale might not fall on an exact tick mark. For
  53   esthetic reasons you might still want the last/first tick mark to fall
  54   on the edges of the scale. By calling <A href="../ref/LinearScale.html#_LINEARSCALE_SETAUTOTICKS">
  55   LinearScale::SetAutoTicks()</A> you tell JpGraph to make the smallest
  56   necessary adjustment of the end/start points so that they fall on an
  57   exact tick mark.</LI>
  58  <LI> Manually specify the tick marks with a call to <A href="../ref/LinearTicks.html#_LINEARTICKS_SET">
  59   LinearTicks::Set()</A> For example<DIV class="phpscript"><CODE><FONT color="#000000">
  60   <FONT color="#0000BB">&nbsp;$graph</FONT><FONT color="#007700">-&gt;</FONT><FONT
  61  color="#0000BB">SetScale</FONT><FONT color="#007700">(</FONT><FONT color="#DD0000">
  62  &quot;textlin&quot;</FONT><FONT color="#007700">,</FONT><FONT color="#0000BB">0</FONT><FONT
  63  color="#007700">,</FONT><FONT color="#0000BB">100</FONT><FONT color="#007700">
  64  );
  65  <BR></FONT><FONT color="#0000BB">$graph</FONT><FONT color="#007700">-&gt;</FONT><FONT
  66  color="#0000BB">yscale</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">
  67  ticks</FONT><FONT color="#007700">-&gt;</FONT><FONT color="#0000BB">Set</FONT><FONT
  68  color="#007700">(</FONT><FONT color="#0000BB">10</FONT><FONT color="#007700">
  69  ,</FONT><FONT color="#0000BB">5</FONT><FONT color="#007700">);</FONT><FONT
  70  color="#0000BB"></FONT></FONT></CODE></DIV>
  71  <P>Will set the major tick marks every at 0,10,20,.. And every minor
  72   tick mark in between (0,5,10,15,20,25,...).</P>
  73  </LI>
  74  </OL>
  75  <P> The three images below illustrates the difference between the
  76   possibilities of ticks for a manual scale.<DIV class="example">
  77  <BR> <A href="exframes/frame_manscaleex1.html" target="blank"><IMG border="0"
  78  HEIGHT="200"  src="img/manscaleex1.png" WIDTH="220"></A>
  79  <BR><B>Figure 72:</B> Manual scale, manual ticks major=7 minor=2 <A href="exframes/frame_manscaleex1.html"
  80  target="blank">[src]</A>&nbsp;
  81  <P></P>
  82  </DIV></P>
  83  <P></P>
  84  <P><DIV class="example">
  85  <BR> <A href="exframes/frame_manscaleex4.html" target="blank"><IMG border="0"
  86  HEIGHT="200"  src="img/manscaleex4.png" WIDTH="220"></A>
  87  <BR><B>Figure 73:</B> Manual scale, automatic ticks with exact limits <A href="exframes/frame_manscaleex4.html"
  88  target="blank">[src]</A>&nbsp;
  89  <P></P>
  90  </DIV></P>
  91  <P></P>
  92  <P><DIV class="example">
  93  <BR> <A href="exframes/frame_manscaleex2.html" target="blank"><IMG border="0"
  94  HEIGHT="200"  src="img/manscaleex2.png" WIDTH="220"></A>
  95  <BR><B>Figure 74:</B> Manual scale, automatic ticks where we allow
  96   adjustments of the limits <A href="exframes/frame_manscaleex2.html" target="blank">
  97  [src]</A>&nbsp;
  98  <P></P>
  99  </DIV></P>
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