• Adobe After Effects Expressions

  Control the number of Decimal points of a random number with a slider control

  Posted by Nawaz Alamgir on March 4, 2019 at 1:20 pm

  Im using

  seedRandom(index,true)
  random(0,100)

  to create a random number, is there a way to control the number of decimal points the random number outputs with a slider control?

  I thought linking a slider using .toFixed(x) would work but it doesn’t

  Anyone?

  Kalleheikki Kannisto replied 7 years, 4 months ago 3 Members · 4 Replies
• 4 Replies

• 

  Nawaz Alamgir

  March 4, 2019 at 1:34 pm

  I managed to figure it out.

  2 sliders one called value which generates the number with this in the source

  seedRandom(index, true)
  random(0,100)

  and another slider with the code

  places = effect("Number of Decimals")("Slider");
val = effect("Value")("Slider"); //sub in the name of your slider here
factor = Math.pow(0.1, places) ;
sign = "";
if (val < 0) sign = "-";
val = Math.abs(val);
whole = Math.floor(val);
fraction = "" + Math.round((val - whole)/factor)*factor;
for (fraction; fraction.length < places+2; fraction+="0");

  sign + whole + "." + fraction.substring(2, places+2)
• 

  Nawaz Alamgir

  March 4, 2019 at 2:00 pm

  But, if you have a better way of doing this please let me know
• 

  Andrei Popa

  March 4, 2019 at 3:51 pm

  Your code is rather complicated. If you have a random number and want to round it to x decimals, just go
  
var myNumber = someRandomNumber;
var multiplicator = Math.pow(10,x);
Math.round(myNumber*multiplicator)/multiplicator;


  To simple things up, multiplicator is 10 if you want a decimat, 100 if you want 2 etc.

  Andrei
  My Envato portfolio.
• 

  Kalleheikki Kannisto

  March 6, 2019 at 9:35 am

  Or
  parseFloat(random(100)).toFixed(Math.round(*pick-whip slider value here*));

  Kalleheikki Kannisto
  Senior Graphic Designer

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