Area function

Syntax: | `a = AREA(x,y)`

The `AREA` function calculates the area enclosed in the polygon specified by the vertex coordinates given in the vector arguments `x` and `y`. 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.

Example

The following code produces the picture below.

     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  = '//RCHAR(PIC)//', acos(-1) = '//RCHAR(ACOS(-1))