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A new version of this scenario was uploaded on Sat Mar 17 21:02:59 UTC 2012 Fixed decimal issue. (Hope I did not mess up anything else trying to fix it :? )
kiarockskiarocks

2012/3/18

Cool! However, in edit mode, it glitches out a lot
danpostdanpost

2012/3/18

@kiarocks, what do you mean by 'it glitches out a lot'? If you are referring to the fact that it will not take certain keys at certain times, then it was meant to be that way. All operations must be included in the entering (ex. '300sin(x/250)' will not be accepted, but '300[b]*[/b]sin(x/250)' will). If that is not what you posted about, please explain.
danpostdanpost

2012/3/18

Anybody else notice any 'glitching out' in edit mode? If so, please, please, explain exactly how it is 'glitching out', so I hopefully could re-produce it, and find and fix the problem.
danpostdanpost

2012/3/18

For extreme expressions (either very long or very complicated), I did get some stack overflow errors. Probably need to increase the stack space for this one. I did like the effect of y = cos(x^2) out past x = 50 through 270 or so.
kiarockskiarocks

2012/3/18

It glitches out means sometimes i can see the graph while in edit mode, sometimes edit mode disappears for a second.
kiarockskiarocks

2012/3/18

Also, no θ?
danpostdanpost

2012/3/18

I have not seen that! In Greenfoot on my computer, in the .jar application, nor on the site. If anyone else experiences what kiarocks has, please advise. Thanks in advance.
kiarockskiarocks

2012/3/18

Could it be because I am using java 6?
danpostdanpost

2012/3/18

@kiarocks, I could not say for sure about you using java 6 being the issue. As far as the 'theta' symbol, I think it would be best for me to resolve the stack space issue first, as making things more complicated and adding more method calls would just add insult to injury, if you know what I mean. I already have methods calling methods, that recall methods, etc. to parse formulas input by users.
A new version of this scenario was uploaded on Sun Mar 18 16:35:50 UTC 2012 Including source.
A new version of this scenario was uploaded on Sun Mar 18 18:58:25 UTC 2012 Fixed stack overflow problem.
kiarockskiarocks

2012/3/19

Now for theta?
kiarockskiarocks

2012/3/19

Just tested cos(x pow 2) and works perfectly!
danpostdanpost

2012/3/19

Thanks, kiarocks.
kiarockskiarocks

2012/3/21

I tried y=abs((x^2+x^3)^(1/3)+abs(x)) and it was different than on my computers grapher. Java or bug?
danpostdanpost

2012/3/21

@kiarocks, I could not say. Find a x value where they are different, and find out which has the y value that is correct. Then report back.
danpostdanpost

2012/3/21

I do not think Math.pow can handle taking negative numbers to non-integer powers.
A new version of this scenario was uploaded on Wed Mar 21 21:13:47 UTC 2012 Forced cbrt as opposed to pow(1/3).
danpostdanpost

2012/3/21

@kiarocks, does it match your computers grapher now? (I made it so when the exponent was '1/2' or '1/3', it would use Math.sqrt or Math.cbrt, instead of using Math.pow(factor, exponent)).
joshbuhljoshbuhl

2013/3/17

Hi Dan, I'm a public schools teacher and I'd love to use this as a base in a c.s. course for 13th graders to implement some numeric methods like Newton's Method for finding roots. The green comment box states that it was uploaded with source, but there's no "open in greenfoot" and I can't find another way to download it (and I'm new here, so maybe I'm just missing something...). cheers, j
danpostdanpost

2013/3/17

@joshbuhl, no. You are not missing anything. I did not think I had included to source to this at any time, but it does appear that I had. Do you need the code as well, or just the application?
danpostdanpost

2013/3/17

For the application, if you can give me your e-mail address, I would be glad to forward it to you. If you do not wish to publicly show your e-mail address, click on my user picture, open my 'Private Messaging' scenario and supply it to me there. Then, post a note that you had done so, here.
joshbuhljoshbuhl

2013/3/17

Great! Iwould appreciate the source, since I would modify it. Be happy to post/send you the result, though. I've sent you a pm (how the heck does your app get the user data?!) Thanks! j
kiarockskiarocks

2013/3/17

@danpost, the equation I tested a year ago (I can't believe how long I've been programming) works properly.
LéaCristolLéaCristol

2013/4/8

I am very interested in your program. Can you send me the source code Greenfoot? Thank you in advance. (leacristol@hotmail.fr)
A new version of this scenario was uploaded on 2015-06-16 06:25:34 UTC