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<HTML>
<HEAD>
<TITLE>Area function</TITLE>
</HEAD>
<BODY bgcolor="#FFFFFF" fgcolor="#000000">
<P><font size="+3" color="green"><B>Area function</B></font></P>
<P>
<TABLE border="1" cols="2" frame="box" rules="all" width="572">
<TR>
<TD width="15%" valign="top"><B>Syntax</B>:</TD>
<TD width="85%"><CODE>
a = AREA(x,y)</CODE>
</TD></TR>
</table></p>
<p>
The <CODE>AREA</CODE> function calculates the area
enclosed in the polygon specified by the vertex coordinates given in the vector
arguments <code>x</code> and <code>y</code>. Both vector arguments must be of the
same length. The polygon need not be closed, that is, the last point will be
assumed to connect to the first point.</p>
<P>
<font size="+1" color="green">Example</font></P>
<p>
The following code produces the picture below.</P>
<P>
<font color="blue"><pre>
GENERATE THETA 0 .25 360
R[1:LEN(THETA)] = 1
SET AUTOSCALE COMMENSURATE
GRAPH R*COSD(THETA) R*SIND(THETA)
PIC = AREA(R*COSD(THETA),R*SIND(THETA))
SET TEXTALIGN 2
SET %XTEXTLOCATION 50
SET %YTEXTLOCATION 90
SET TEXTINTERACTIVE 0
TEXT 'Calculated <pi> = '//RCHAR(PIC)//', acos(-1) = '//RCHAR(ACOS(-1))
</pre></font></P>
<P>
<center><IMG SRC="area1.png"></center></P>
<P>
<a href="../Airy/airy.htm"><img align=middle border="0" src="../../../shadow_left.gif">
<font size="+1" color="olive">Airy's functions</font></a><br />
<a href="../Bessel/bessel.htm"><img align=middle border="0" src="../../../shadow_right.gif">
<font size="+1" color="olive">Bessel functions</font></a>
</P>
</BODY>
</HTML>
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