thanks, that actually helped in a different way. a follow up: is there a way to square or use other exponents in [expr]? I'm basically trying to code Euclidean distance formula in one [expr] without having to use [pow 2] and [sqrt] (the latter of which I know I can use in the formula as sqrt(x)). What I think all of this should look like:

[expr sqrt(pow2(abs($f1 - $f3) + abs($f2 - $f4)))]

Getting hung up on "pow2" part

It just occurred to me that maybe there is already an external that does this and I don't know about it.

thanks,

hdez

http://www.pdpatchrepo.info/hurleur/euclidean-distance.pd

Are there Pd Objects for vector translations? Do you mean a matrix translation? What's the diff?
For the unitiated: Vectors used by graphics software are usually 3-dimensional datatypes which describe location as a coordinate vector(that's the XYZ ), or a euclidean vector: usually represents acceleration, velocity or somesuch. There is sadly no 'vanilla' public vector object in Pd(that I've found), making 'from scratch' particle generators and physics impossible.

I'm no linear algebra ringer, so please correct me if you can.

I'm assuming that the rotation and translation objects in GEM are essentially matrix math objects, affecting the current location vector of the Gl chain (the GEM chain, basically). When you create an instance of [translateXYZ x y z], you are applying a translation matrix:

1 0 0 x
0 1 0 y
0 0 1 z
0 0 1 1

Check it out on wikipedia for all the hairy details.

Hi there,
I am reasonably new to Pure Data. I am doing my final year project in it. My question at the moment is this. I have an electronic drum kit rigged up to pd. There are 8 input channels. Six of the input pads register the velocity of the hit, the other two pads are pedals with just an on/off state. I want to use one of the pedals to start recording the output and when it is kicked again to stop recording and play it back in order to create layered polyrhythms. What is the best means to achieve this affect?
Thanks in advance,
Ailbhe

Hi,
I'm having trouble to build a patch to measure the EUCLIDEAN DISTANCE between arrays (fiiled w/ audio data). I've started using expr~ to build the: pow($v2-$v1),2) but I couldn't make the 'sum' fction work in order to give the sum of the array N pts.

Attached is a PD patch ilustrating it.... Any help is appreciated,
Thanks!
J

http://www.pdpatchrepo.info/hurleur/exprSumIssue.pd