I Am teaching an "Engineering Design" class to a group of 6th graders
here in Vermont. We will be monitoring temperatures outdoors and in a
greenhouse.  We have the sensor stuff all worked out. BUT we will soon
need to display GRAPHS of temperature VS time.

ISTHERE an available UNIT 'out there' with easy-to-use line graphs
etc??  The students are programming the mainline stuff here, and doing
the overall designs, but I am providing high-level interfaces for them
to use for things that are not appropriate for their level of skill
yet.  I do understand the facilities in the GRAPH unit, and I CAN write
some higher-level stuff, but I HOPE we can reuse some existing work!
(We are using TP7.0, and VGA displays)...

We looked thru some of the FAQ's and sites but this didn't jump out at
us. Any help/suggestions are welcome.

Any suggestions on age-appropriate tutorial material (6th grade : 12
years old) would be appreciated.

Regards,

program random1 (input, output);                 { random1.pas }

{ from adv. turbo pascal, schildt, p. 192, comparison of 3 random
  number generators, for my tp 4.0 }

uses crt, graph3;

const   count = 1000;

var     freq1, freq2, freq3 : array[0..9] of integer;
        a1, a2, x, y : integer;
        f, f2, f3, r, r2, r3 : real;

procedure display;

var    t : integer;

begin

   for t := 0 to 9 do
   begin
      draw(t*10,180,t*10,180-freq1[t],2);
      draw(t*10+110,180,t*10+110,180-freq2[t],2);
      draw(t*10+220,180,t*10+220,180-freq3[t],2);
   end;
end;     { end display }

function ran1: real;
var   t: real;
begin
   t := (a1*32749+3) mod 32749;
   a1 := trunc(t);
   ran1 := abs(t/32749);
end;     { end ran1 }

function ran2: real;
var   t: real;
begin
   t := (a2*10001+3) mod 17417;
   a2 := trunc(t);
   ran2 := abs(t/17417);
end;    { end ran2 }

begin
   graphcolormode;
   palette(1);                       { setup for color graphics w/
palette 1 or 0,1,2,3 }

   gotoxy (10,1);
   write ('comparison of random');
   gotoxy (12,2);
   write ('number generators');
   draw (0,180,90,180,3);
   draw (110,180,200,180,3);
   draw (220,180,310,180,3);
   gotoxy (5,25);
   write ('random     ran1     ran2');

   a1 := 1;                          { initialize random generator
variables }
   a2 := 203;
   f := 0;
   f2 := 0;
   f3 := 0;

   for x := 0 to 9 do
   begin                             { initialize frequency arrays }
      freq1[x] := 0;
      freq2[x] := 0;
      freq3[x] := 0;
   end;

   for x := 1 to count do
   begin
      r := random;                   { get a random number }
      f := f + r;                    { add a computation mean }
      y := trunc (r * 10);           { convert to integer from 0 t 9 }
      freq1[y] := freq1[y] + 1;      { increment frequency count }

      r2 := ran1;
      f2 := f2 + r2;
      y := trunc (r2 * 10);
      freq2[y] := freq2[y] + 1;

      r3 := ran2;
      f3 := f3 + r3;
      y := trunc (r3 * 10);
      freq3[y] := freq3[y] + 1;

      display;                       { graph frequency counts }
   end;

   readln;

   textmode (c80);                   { return screen to text mode }

   writeln ('mean of ramdom is : ',f/count);
   writeln ('mean of ran2 is : ',f2/count);
   writeln ('mean of ran3 is : ',f3/count);

To the original question, what's wrong with the GRAPH unit?  The concept of
using may be a little more difficult for a 6th grade class, but there's no
reason you couldn't write some wrapper functions which would make things
easier (such as scaling, setting the axes, drawing scaled bars, etc.)  The
unit you write would certainly be reusable.

Re: Graphs UNIT??

Well, I took a good look at the BGIDEMO program. Sure, I can do this,
but it will be 8 to 16 hours to do something good, flexible,
reuseable.  SOMEBODY must have Been Here Before with Turbo.?? Anyone??