/usr/share/doc/plplot-doc/html/scales.html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
<HTML
><HEAD
><TITLE
>Defining Plot Scales and Axes</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK
REL="HOME"
TITLE="The PLplot Plotting Library"
HREF="index.html"><LINK
REL="UP"
TITLE="Simple Use of PLplot"
HREF="simple.html"><LINK
REL="PREVIOUS"
TITLE="Initializing PLplot"
HREF="initializing.html"><LINK
REL="NEXT"
TITLE="Labeling the Graph"
HREF="labelling.html"><LINK
REL="STYLESHEET"
TYPE="text/css"
HREF="stylesheet.css"></HEAD
><BODY
CLASS="sect1"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>The PLplot Plotting Library: Programmer's Reference Manual</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="initializing.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Chapter 2. Simple Use of PLplot</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="labelling.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="sect1"
><H1
CLASS="sect1"
><A
NAME="scales"
>Defining Plot Scales and Axes</A
></H1
><P
>&#13;      The function <A
HREF="plenv.html"
><CODE
CLASS="function"
>plenv</CODE
></A
> is used to define the scales and axes for simple
      graphs.  <A
HREF="plenv.html"
><CODE
CLASS="function"
>plenv</CODE
></A
> starts a new picture on the next subpage (or a new
      page if necessary), and defines the ranges of the variables required.
      The routine will also draw a box, axes, and numeric labels if
      requested.  The syntax for <A
HREF="plenv.html"
><CODE
CLASS="function"
>plenv</CODE
></A
> is:
    </P
><P
>&#13;      <DIV
CLASS="funcsynopsis"
><P
></P
><A
NAME="AEN238"
></A
><TABLE
CLASS="funcprototype"
><TR
><TD
><CODE
CLASS="FUNCDEF"
>&#13;	    plenv
	  </CODE
>(xmin, xmax, ymin, ymax, just, axis);</TD
></TR
></TABLE
><P
></P
></DIV
>
    </P
><TABLE
CLASS="variablelist"
><TR
><TD
><DL
><DT
><CODE
CLASS="parameter"
>xmin, xmax</CODE
>
	  (<TT
CLASS="literal"
>PLFLT</TT
>, input)</DT
><DD
><P
>&#13;	    The left and right limits for the horizontal axis.
	  </P
></DD
><DT
><CODE
CLASS="parameter"
>ymin, ymax</CODE
>
	  (<TT
CLASS="literal"
>PLFLT</TT
>, input)</DT
><DD
><P
>&#13;	    The bottom and top limits for the vertical axis.
	  </P
></DD
><DT
><CODE
CLASS="parameter"
>just</CODE
>
	  (<TT
CLASS="literal"
>PLINT</TT
>, input)</DT
><DD
><P
>&#13;	    This should be zero or one.  If <CODE
CLASS="parameter"
>just</CODE
> is
	    one, the scales of the x-axis and y-axis will be the same (in
	    units per millimeter); otherwise the axes are scaled
	    independently.  This parameter is useful for ensuring that
	    objects such as circles have the correct aspect ratio in the
	    final plot.
	  </P
></DD
><DT
><CODE
CLASS="parameter"
>axis</CODE
>
	  (<TT
CLASS="literal"
>PLINT</TT
>, input)</DT
><DD
><P
>&#13;	    <CODE
CLASS="parameter"
>axis</CODE
> controls whether a box, tick marks,
	    labels, axes, and/or a grid are drawn.
	  </P
><P
></P
><UL
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = -2: No box or annotation.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = -1: Draw box only.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 0: Draw box, labeled with
		coordinate values around edge.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 1: In addition to box and labels,
		draw the two axes X = 0 and Y = 0.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 2: Same as
		<CODE
CLASS="parameter"
>axis</CODE
> = 1, but also draw a grid at the
		major tick interval.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 10: Logarithmic X axis, linear Y
		axis.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 11: Logarithmic X axis, linear Y
		axis and draw line Y = 0.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 20: Linear X axis,
		logarithmic Y axis.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 21: Linear X axis, logarithmic Y
		axis and draw line X = 0.
	      </P
></LI
><LI
><P
>&#13;		<CODE
CLASS="parameter"
>axis</CODE
> = 30: Logarithmic X and Y axes.
	      </P
></LI
></UL
></DD
></DL
></TD
></TR
></TABLE
><P
>&#13;      Note: Logarithmic axes only affect the appearance of the axes and
      their labels, so it is up to the user to compute the logarithms prior
      to passing them to <A
HREF="plenv.html"
><CODE
CLASS="function"
>plenv</CODE
></A
> and any of the other routines.  Thus, if a
      graph has a 3-cycle logarithmic axis from 1 to 1000, we need to set
      <CODE
CLASS="parameter"
>xmin</CODE
> =
      <CODE
CLASS="function"
>log<SUB
>10</SUB
></CODE
>(1) = 0.0, and
      <CODE
CLASS="parameter"
>xmax</CODE
> =
      <CODE
CLASS="function"
>log<SUB
>10</SUB
></CODE
>(1000) = 3.0.
    </P
><P
>&#13;      For greater control over the size of the plots, axis labeling and
      tick intervals, more complex graphs should make use of the functions
      <A
HREF="plvpor.html"
><CODE
CLASS="function"
>plvpor</CODE
></A
>, <A
HREF="plvasp.html"
><CODE
CLASS="function"
>plvasp</CODE
></A
>, <A
HREF="plvpas.html"
><CODE
CLASS="function"
>plvpas</CODE
></A
>, <A
HREF="plwind.html"
><CODE
CLASS="function"
>plwind</CODE
></A
>, <A
HREF="plbox.html"
><CODE
CLASS="function"
>plbox</CODE
></A
>, and routines for
      manipulating axis labeling <A
HREF="plgxax.html"
><CODE
CLASS="function"
>plgxax</CODE
></A
> through <A
HREF="plszax.html"
><CODE
CLASS="function"
>plszax</CODE
></A
>.
    </P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="initializing.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="labelling.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>Initializing PLplot</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="simple.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>Labeling the Graph</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>
plplot-doc 5.9.9-2ubuntu2 / usr / share / doc / plplot-doc / html / scales.html
