Hi everyone,

I'm sure there's an easy way to do this but the more I dig into it the uglier my patching is getting. Can anyone show me a simple way to dynamically change the operation in an expre~ statement such as:

[expr~ $1 < $2]

I'd like to use radio buttons or something similar to be able to change the < to ==, &&, and others in the patch to achieve different sounds.

I'm taking a snippet (well more than a snippet) from Derek Holzer's tutorial on synth building here: http://en.flossmanuals.net/PureData/SquarewavesAndLogic (scroll to bottom) if you'd like to see more of the context.

Thanks in advance...

Bill

you could use a pair of gates, have each of the outlets going to a different operator.

alternatively, probably better, you could use several semicolonated expressions and have the radio button control a switch to select the outlets.

or you could use if:

expr if ($f1 == 1, $f2 > $f3, if ($f1 == 2, $f2 == $f3, 0))

hope that helps!

Hi Yas,

Thanks, I tried some of that before couldn't get it...I've figured out a semicolon approach with a fake spigot like patch...here's what i've done...

#N canvas 0 0 450 300 10;
#X obj -246 1 dac~;
#X obj -304 -29 *~;
#X floatatom -291 -46 1 0 0 0 - - -;
#X msg -287 -70 1;
#X msg -316 -72 0;
#X obj -293 -104 bng 15 250 50 0 empty empty empty 0 -6 0 10 -262144
-1 -1;
#X obj -239 -29 *~;
#X floatatom -226 -46 1 0 0 0 - - -;
#X msg -222 -70 1;
#X msg -251 -72 0;
#X obj -235 -104 bng 15 250 50 0 empty empty empty 0 -6 0 10 -262144
-1 -1;
#X obj -174 -30 *~;
#X floatatom -161 -47 1 0 0 0 - - -;
#X msg -157 -71 1;
#X msg -186 -73 0;
#X obj -171 -103 bng 15 250 50 0 empty empty empty 0 -6 0 10 -262144
-1 -1;
#X obj -142 -130 expr~ $v1 == $v2 \; $v1 && $v2 \; $v1 || $v2;
#X text -295 -121 ==;
#X text -237 -122 &&;
#X text -173 -126 ||;
#X connect 1 0 0 0;
#X connect 1 0 0 1;
#X connect 2 0 1 1;
#X connect 3 0 2 0;
#X connect 4 0 2 0;
#X connect 5 0 3 0;
#X connect 5 0 9 0;
#X connect 5 0 14 0;
#X connect 6 0 0 0;
#X connect 6 0 0 1;
#X connect 7 0 6 1;
#X connect 8 0 7 0;
#X connect 9 0 7 0;
#X connect 10 0 8 0;
#X connect 10 0 14 0;
#X connect 10 0 4 0;
#X connect 11 0 0 0;
#X connect 11 0 0 1;
#X connect 12 0 11 1;
#X connect 13 0 12 0;
#X connect 14 0 12 0;
#X connect 15 0 13 0;
#X connect 15 0 9 0;
#X connect 15 0 4 0;
#X connect 16 0 1 0;
#X connect 16 1 6 0;
#X connect 16 2 11 0;

thanks....

i would use multiple expr and a demultiplexer:

|expr >| |expr ==| |0/1| from toggle
| | |
|demux 1 2_____________|

with expr~ you may want to use a mux too
it COULD reduce computational overhead

If you want to reduce cpu load, just using [mux~] isn't going to cut it. Even though [mux~] is only letting one of its inlets through its outlet, those [expr~]s are still running. You need to turn off the processing for each [expr~] using [switch~]. For this application it's probably negligible, but here's how I would do it.

http://www.pdpatchrepo.info/hurleur/selectoperator.mmb.pd

Great thanks guys...I'll plug this in to the app and see how it goes...

bill

Actually, is I'm only using one expr with different argumtents, does that count as expr for each? Can anyone tell me if my solution below is less efficient than Maelstorm's?

Thanks,

bill

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

yes but in this case it shouldn't be important
but quiet ugly
especially if you still want to control it with radio buttons
if you want the cleanest patch try mine
if you want the most efficient mmb's

Thanks..yep, ugly it is...I have to admit though, that I couldn't figure out how to patch your example...still don't use PD enough to get it from the diagram. If you or anyone else had time to knock it together for me, I'd appreciate, but don't worry if not, as my ugly version works (it's not like the patch that it's in is pretty either, it's a mess too haha.

Thanks,

Bill

try around a bit more and use right click / help
look at mmb's version its useful if you have heavy stuff going on
<ctrl + b> work your way through 2. and 3. (you don't have to understand everything)
if you are done work through 5.

Actually, is I'm only using one expr with different argumtents, does that count as expr for each

well it works that way but i guess its a little bit cheaper
less connections and technically only one object
but i bet its negligible

oh and here take this
its dangerous to go alone

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

Cool, slur, thanks for that....makes more sense seeing it,

Bill