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qnanqing presents ...

2011/8/25

# Grapher

I think its fun to see some mathematical graph so i made it in Greenfoot! :D Well its done now :D
Although itsnt finished yet..
Still learning about RPN and want to make one RPN parser :D

The source is very very messed up! Its not even an object oriented programming! :P Its just a scratch.

I'll clean the source later for documentation.

update 3/11/2011
The source code is now more Object Oriented

Disabled the zoom function (because the code isnt "honest" (not Object Oriented) :P )
Added mouse information, and map location on the screen.
Supported map drag

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a) red b) blue c) yellow d) green Also, to be able to read in dynamic equations, there are several routes you could go. One is to build a simple parser for the the input (which would not be very simple to code probably). The other that I can think of is to implement a drag and drop interface for math operations so that you know for certain what has been entered. For example, to add two expressions, you could have a icon to drag in that has two placeholders for the expressions on either side of the "+" symbol, kind of like so: 2x == () * () -> (2) * (x) 2(x+1) == () * (() + ()) -> (2) * ((x)+(1)) That way, you know what the equation parses to in advance because you force it to behave that way. The other way I can think of, and probably the easiest is to implement is a parser that uses prefix, function notation. So your equation c for example could be written like so: subtract( sqrt( abs( mult(x,10) ) ) , 10 ); Of course, that looks a bit messier, but it's one of the easier ways to do it. I hope this was helpful.
A new version of this scenario was uploaded on Thu Nov 03 15:38:47 UTC 2011 Disabled the zoom function (because the code isnt "honest") :P Added mouse information, and map location on the screen. Supported map drag
qnanqing

2011/11/3

@supermagicmilk sorry for the late reply! i think i will use RPN for the parser, so now im working with the RPN parser (but first in different scenario!) :D
A new version of this scenario was uploaded on 2019-03-27 04:05:06 UTC Update to recent version of Greenfoot.
A new version of this scenario was uploaded on 2019-03-27 04:41:40 UTC Migrate from java.awt.Color to greenfoot.Color
A new version of this scenario was uploaded on 2019-03-27 04:42:11 UTC Migrate from java.awt.Color to greenfoot.Color