графики функций в паскале abc

Ответ от ?Pandacrash[гуру]
program example;
uses graphabc;
var
sx,sy: real;
x,y,bufx,bufy:integer;
const
xs=-10;
xe=10;
ys=0;
ye=100;
dx=0.5;
x0=Round(windowwidth/2);
y0=Round(windowheight/2);
function PToDX(x_:real):integer;
begin
result:=Round(x0+(window.width/2*x_)/xe);
end;
function PToDY(y_:real):integer;
begin
result:=Round(y0-(window.height/2*y_)/ye);
end;
BEGIN
pen.Color:=clBlack;
pen.Width:=2;
moveto(0,y0);
lineto(window.width,y0);
moveto(x0,0);
lineto(x0,window.height);
pen.Color:=clGreen;
pen.Width:=1;
sx:=xs;
x:=PToDX(sx);
sy:=sqr(sx);
y:=PToDY(sy);
moveTo(x, y);
while(sx <= xe) do
begin
sy:=sqr(sx);
y:=PToDY(sy);
lineTo(x, y);
//X
if (Frac(sx)=0) then
begin
if sx=xe then textout(x-15,y0+3,sx)
else textout(x-5,y0+3,sx);
pen.Color:=clBlack; pen.Width:=2;
moveto(x,y0-3); lineto(x,y0+3);
pen.Width:=1;
pen.Color:=clRed;
Circle(x,y,2);FloodFill(x,y,clRed);
end;
//Y
pen.Color:=clBlack; pen.Width:=2;
if (Frac(sy)=0) then
begin
if sy=ye then textout(x0+3,y,sy)
else textout(x0+5,y-8,sy);
moveto(x0-3,y); lineto(x0+3,y);
end;
pen.Width:=1;
pen.Color:=clGreen;
moveto(x,y);
sx:=sx+dx;
x:=PToDX(sx);
end;
end.

Ответ от 3 ответа[гуру]