
DPNTLINEName:
The formula for this distance is
where the line is defined as
B = Y2  s*X2
<SUBSET/EXCEPT/FOR qualification> where <x1> is a variable or a parameter containing the x coordinates of the first point; <y1> is a variable or a parameter containing the y coordinates of the first point; <x2> is a variable or a parameter containing the x coordinates of the second point; <y2> is a variable or a parameter containing the y coordinates of the second point; <slope> is the slope of the line containing (<x2>,<y2>); <dist> is a variable or a parameter (depending on what the input arguments are) where the computed perpindicular distances are stored; and where the <SUBSET/EXCEPT/FOR qualification> is optional.
LET DIST = DPNTLINE(X1,Y1,X2,Y2,SLOPE)
skip 25 read convhull.dat x y . let y2 x2 = 2d convex hull y x let xtemp = x2(1) let ytemp = y2(1) let y2 = combine y2 ytemp let x2 = combine x2 xtemp let x3 = x2 let y3 = y2 let n = size y2 let nm1 = n  1 retain x2 y2 for i = 1 1 nm1 retain x3 y3 for i = 2 1 n let slope = slope(x2,y2,x3,y3) let pdist = dpntline(xtemp,ytemp,x3,y3,slope) . set write decimals 4 print "Anchor Point: (^xtemp,^ytemp)" print " " print " " print x3 y3 slope pdistThe following output is generated Anchor Point: (0,2.)  X3 Y3 SLOPE PDIST  1.0000 1.7300 0.2700 0.0000 1.7300 1.0000 1.0000 0.3650 2.0000 0.0000 3.7037 0.3674 1.7300 1.0000 3.7037 0.6392 1.0000 1.7300 1.0000 2.3650 0.0000 2.0000 0.2700 3.7282 1.0000 1.7300 0.2700 3.7282 1.7300 1.0000 1.0000 2.3650 2.0000 0.0000 3.7037 0.6392 1.7300 1.0000 3.7037 0.3674 1.0000 1.7300 1.0000 0.3650 0.0000 2.0000 0.2700 0.0000
Date created: 02/15/2013 