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'Circular' Scaling Question


Medd

Medd
Aug 26, 2011 at 12:18pm

'Circular' Scaling Question

Hello all,

Mathematics related problem, maybe someone with more knowledge can help me out:

I’m currently scaling 0. to 360. to get -180. to 180. so that 180. = 0.

I’d also like to scale 0. to 360. to get 90. to 90. so that 180. = -90.

I hope that makes enough sense? Sorry maths isn’t my strong point, I’ve encountered difficult problems before and found my way via trial and error but this has me stumped.

Thanks

#58635

Medd

Medd
Aug 26, 2011 at 12:38pm

This is what I have so far, got to be a simpler way:

– Pasted Max Patch, click to expand. –

#210816

Medd

Medd
Aug 26, 2011 at 12:49pm

DEvo – What I mean is it needs to stay within the -180. to 180. range but 0. needs to equal 90. rather than -180.

#210817

FRid

FRid
Aug 26, 2011 at 12:49pm

Isn’t this the first one? The second one is a bit more tricky. I’ll see if i can wrap my head around that one.

`

– Pasted Max Patch, click to expand. –

We almost posted simultaneous, i think you need a sin/cos/tan function for that.

#210818

Medd

Medd
Aug 26, 2011 at 12:51pm

Yes FRid that’s right, that was no problem. As you say the second problem is trickier and my patch doesn’t do it very cleanly.

Thanks for the input and interest so far! I have faith someone can help me!

#210819

Medd

Medd
Aug 26, 2011 at 1:12pm

Attached a rough diagram demonstrating what I mean. Sorry for any confusion!

[attachment=169705,2577]

Attachments:
  1. CircScale.png
#210820

Medd

Medd
Aug 26, 2011 at 1:40pm

This is my best solution so far, realised I didn’t need that gate before:

– Pasted Max Patch, click to expand. –

#210821

pm

pm
Aug 26, 2011 at 2:21pm

You could also use [% 360] to get what you need.

– Pasted Max Patch, click to expand. –
#210822

FRid

FRid
Aug 26, 2011 at 2:22pm

Ah man. I wish i had paid more attention during class. Feels a bit like cheating.

– Pasted Max Patch, click to expand. –

This one is correct

#210823

FRid

FRid
Aug 26, 2011 at 2:30pm

Oops, no not correct according to the diagram. I focussed too much on the 0. 360. >> 90. 90. my bad.

Concerning the diagram whats up with -180/180 in the innercircle? And won’t poltocar/cartopol help out here somehow?

#210824

Medd

Medd
Aug 26, 2011 at 2:31pm

Thanks for all of the suggestions, I’ve now got several methods to compare. What a nice brain workout eh?

FRid – the 180/-180 is the overlap for each side of the circle. 0 to 180 on one side 0 to -180 on the other. Sorry that was a quick Paintbrush diagram.

#210825

FRid

FRid
Aug 26, 2011 at 2:46pm

That was also my bad (again!) After taking a second look i got it. Maybe i should start paying more attention in general :) And these are nice puzzles indeed.

FRid

@ p.m. Nice one! Somehow the “funny” symbols remain obscure to me

#210826

pm

pm
Sep 1, 2011 at 12:29pm

[%] The funny symbol? :) That’s a good way to call it.
The modulo is perfectly suited for circular operation since it will always output a value within a given range, whatever is the input. Combining a [% 360] with a [-180], you will always get a output within -180,180. If you want that to be scaled, just do the scale operation before.

– Pasted Max Patch, click to expand. –
#210827

FRid

FRid
Sep 7, 2011 at 7:15pm

Yeah, i didn’t have a better description at hand. For some reason i focussed too much on the exclamation-mark family of operators and modulo never really came to mind.

Thanks for the heads up,
FRid

#210828

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