Sample Problems > Usage > Misc

{ REPEAT.PDE

This example illustrates the use of the REPEAT statement to generate

repetitive structures, and the string facility for creating labels.

}

title 'REPEAT and $string test'

Variables

definitions

a = 1

{ a list of X-coordinates: }

xc=array(1/3, 2/3, 3/3, 4/3, 5/3)

{ a list of Y-coordinates: }

yc=array(1/3, 2/3, 3/3, 4/3, 5/3)

rad = 0.1 { radius of circular dots }

s = 0

equations

U: div(a*grad(u)) + s = 0;

boundaries

region 1

start(0,0)

value(u)=0

line to (2,0) to (2,2) to (0,2) to close

region 2

a = 0.05

s = 4*magnitude(x-1,y-1)

repeat i=1 to 5 { an indexed loop on X-position }

repeat j=1 to 5 { an indexed loop on Y-position }

{ an array of circular dots at the tabulated coordinates }

start "Loop"+$i+$j (xc[i]+rad,yc[j]) {construct loop name using string conversion }

arc(center=xc[i],yc[j]) angle=360

endrepeat

monitors

contour(u)

plots

contour(u) painted

surface(u)

surface(s) as "Source"

repeat i=1 to 5

repeat j=1 to 5

elevation(u) on 'loop'+$i+$(j)

endrepeat

end