Randomly picking from set value list

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How does one create an expression where the value would be randomly picked from a list of 9 pre-determined values.

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Depending on your seed you can do this using Python:

import random
random.seed(lvar('PT'))
return random.choice()
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What about using hscript or VEX rand() in conjunction with fit01().

i.e:
hscript
fit01(rand($PT), 0, 9)

or
VEX
fit01(rand(@ptnum), 0, 9)
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PradeepBarua
What about using hscript or VEX rand() in conjunction with fit01().

i.e:
hscript
fit01(rand($PT), 0, 9)

or
VEX
fit01(rand(@ptnum), 0, 9)

The values would not be 0-9. There would be 9 float values, each different.
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pusat
Depending on your seed you can do this using Python:

import random
random.seed(lvar('PT'))
return random.choice()

Excellent - Thank you!
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firefly9000
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Depending on your seed you can do this using Python:

import random
random.seed(lvar('PT'))
return random.choice()

Excellent - Thank you!

How did you make sense of that? …would anyone please care to elaborate? I'm after the same thing here. Even simpler, trying to randomly pick among a short list of values (0, 90, 180, 270, 360) to create orientation randomness on some objects scattered using a copy node, but restricting them to those orientations only.

Cheers,

A.
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Adriano
firefly9000
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Depending on your seed you can do this using Python:

import random
random.seed(lvar('PT'))
return random.choice()

Excellent - Thank you!

How did you make sense of that? …would anyone please care to elaborate? I'm after the same thing here. Even simpler, trying to randomly pick among a short list of values (0, 90, 180, 270, 360) to create orientation randomness on some objects scattered using a copy node, but restricting them to those orientations only.

Cheers,

A.

I can't help you on the python part as I'm pretty rusty with python, but doing what you want in vex is fairly simple.

// create random integer from 0-3 generated from the point number, then multiply that by 90
float randVal = rand(@ptnum);
int degreeRotation = int(fit(randVal ,0,1,0,4)) * 90;

// @rot is a quaternion value a copy node will inherently read, you can also use other attributes like transform/orient/up etc…

float angle = radians(degreeRotation);
vector axis = {0,1,0};
@rot = quaternion(angle, axis);

hope that helps
Edited by electricalpencil - Feb. 15, 2018 15:37:19
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Thanks man, I wish it did help, but frankly it didn't. Just simple stuff like “int(fit(randVal ,0,1,0,4))” which i assume should return a value between 0 and 1 and be remapped between 0 and 4 and turn it into an integer…. just does not work for me in any context. Houdini gives me an error “unable to evaluate expression, bla di bla…”. So that's not a good start, is it.

Cheers,

A.
Edited by Adriano - March 1, 2018 13:14:21
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In vex it would be (int)float(floor(val*5))to get a value between 0 and 4 (assuming val already contained a random float between 0 and 1 from the rand() function.) You don't want to use fit/round because it won't be evenly distributed.

The hscript expression would be floor(rand(seed)*5), with seed being whatever you are keying the random with, e.g. ($PT, $F, etc)
Edited by jsmack - March 1, 2018 13:57:35
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