Graphing calculator

[Tubs]

alright this graphing calculator works for declaring a point, it puts it whereever i say. BUT whenever i put a slope it draws multiple dots... (and i know it is possible to work cause my friend got it)

whats wrong?

[Tony]

wow dude, your graphing is WAY off... I cant see it actually... here's the correct way of graphing a line:

code:

Graph     for I : -midx .. midx         Y := round (M * I) + midy         drawfilloval(midx + I, Y, 2,2,white)     end for

replace your procedure with that. To get the Y value, you just multiply X (which is counter, so its I) by slope (M) and add midy to bring the graph up so it runs through the middle.

instead of drawing a bunch of dots, just draw a small circle. Adding midx to the X value to bring it to the right so it runs through the middle. (You gotta account for those negative areas of the graph)

I'm glad someone found text effects tutorial useful

[Tubs]

hahaha you noticed that did you

anyways k i will try that gimme 1 sec

[Tubs]

alright it makes the line, but its still all made of dots. how do i make it connected if thats possible? well i know its possible but im really tired lol

AND it messes up my graphing thing. ex, 10 x value and 10 y doesnt go up 1 square

[Tony]

to make dots connected, you ether

a) have to draw more dots. Such as instead of looping 1,2,3 try looping 1.5,2,2.5,3, etc.

you can use only integers in forloop, so use a normal loop instead. OR

b) draw your graph using lines. Such as instead of drawing a dot, draw a line from previous dot to current dot. You'd have to keep track of the last dot drawn.

[Big_Tom]

yes i also need help with this project. I can't get the line to graph correctly i did the same line thing that you told tubs and i still can not get it to work correctly. This slope is correct but the cordinate values are wrong and i dont know how to fix it.

[Asok]

this is because turing coordinates work differently then graphing coordinates. in graphing the orgin (0,0) is in the center. in turing the origin is in the bottom left corner. This is probably why your coordinates are off.

[Tubs]

actually no, the program has its own coordinate system

[Asok]

Nevermind what I said then

[Tubs]

its aight, and i got it to work for you who were wondering

code:

Graph     for I : -midx .. midx         Z := round (M * (I - X) + Y)         drawfilloval (midx + I, Z + midy , 2, 2, 12)     end for

[/code]

[Big_Tom]

I want to know how to make the line an actual line not just composed of ovals. It would clean it up a little bit more.

[Tubs]

ya that would be nice lol but...

i need to know how to declare an array, then use it in a for statement. its for putting coordinates across the graph. ex, array 1..10 is -50 .. 50 then i use the for statement to put them on the screen by a certain amount

[Tony]

to draw a line, you find start point on -midx and end point on midx then you draw a line between them. The only difference is that the line would be 1 pixel wide, not 4.

as for arrays - http://www.compsci.ca/bbs/viewtopic.php?t=366

with explanations and examples.

[Tubs]

for I : 0 .. maxx by 10
for J : -50 .. 50 by 10

Draw.Text (J, I, midy, fontID, white)

end for
end for


this is supposed to draw -50 .. 50 at midy, why doesnt it work? all the vars are declared *i think* can you put the vars and the correct draw command please?

[Asok]

fontID has not been declared.