Random input to ServoOutput

[PiezaKake]

Hi,

I want to create a workflow where every minute one of 6 numbers (20, 60, 100, 140, 180, 220) is randomly selected and used as an input to a ServoOutput node. Can you help me set up the timer and the random number generator?

[banchan86]

I think there might be more "bonsaic" ways of doing it, but I have used a PythonSource operator from the IronPython library with a script like this.

import random
import time

list_of_numbers = [20, 60, 100, 140, 180, 220]

@returns(int)
def generate():
  for i in range(len(list_of_numbers)):
    number = random.choice(list_of_numbers)
    time.sleep(60)
    yield number

You can change the range to the number of iterations you want, independently of the number of elements. Since this is random, you might get an uneven distribution (the same number might appear twice or never).

If you want a pseudo-random selection where each element is only returned once, you have to pop the list:

import random
import time

list_of_numbers = [20, 60, 100, 140, 180, 220]
number_of_iterations = 6

@returns(int)
def generate():
  for i in range(number_of_iterations):
    index = random.randint(0, len(list_of_numbers) - 1)
    number = list_of_numbers.pop(index)
    time.sleep(60)
    yield number

Be careful not to use the length of the number list for range if you are popping the list at the same time.

[bruno-f-cruz]

For your specific case you can do:

Workflow (Copy+Paste me)

<?xml version="1.0" encoding="utf-8"?>
<WorkflowBuilder Version="2.8.5"
                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
                 xmlns:wie="clr-namespace:Bonsai.Windows.Input;assembly=Bonsai.Windows.Input"
                 xmlns:rx="clr-namespace:Bonsai.Reactive;assembly=Bonsai.Core"
                 xmlns:p1="clr-namespace:Bonsai.Numerics.Distributions;assembly=Bonsai.Numerics"
                 xmlns:scr="clr-namespace:Bonsai.Scripting.Expressions;assembly=Bonsai.Scripting.Expressions"
                 xmlns:io="clr-namespace:Bonsai.IO;assembly=Bonsai.System"
                 xmlns="https://bonsai-rx.org/2018/workflow">
  <Workflow>
    <Nodes>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="wie:KeyDown">
          <wie:Filter>None</wie:Filter>
          <wie:SuppressRepetitions>false</wie:SuppressRepetitions>
        </Combinator>
      </Expression>
      <Expression xsi:type="rx:SelectMany">
        <Name>Sample</Name>
        <Workflow>
          <Nodes>
            <Expression xsi:type="Combinator">
              <Combinator xsi:type="p1:CreateDiscreteUniform">
                <p1:Lower>0</p1:Lower>
                <p1:Upper>5</p1:Upper>
              </Combinator>
            </Expression>
            <Expression xsi:type="Combinator">
              <Combinator xsi:type="p1:Sample" />
            </Expression>
            <Expression xsi:type="scr:ExpressionTransform">
              <scr:Expression>it * 40 + 20</scr:Expression>
            </Expression>
            <Expression xsi:type="Combinator">
              <Combinator xsi:type="rx:Take">
                <rx:Count>1</rx:Count>
              </Combinator>
            </Expression>
            <Expression xsi:type="WorkflowOutput" />
          </Nodes>
          <Edges>
            <Edge From="0" To="1" Label="Source1" />
            <Edge From="1" To="2" Label="Source1" />
            <Edge From="2" To="3" Label="Source1" />
            <Edge From="3" To="4" Label="Source1" />
          </Edges>
        </Workflow>
      </Expression>
      <Expression xsi:type="Combinator">
        <Combinator xsi:type="io:WriteLine" />
      </Expression>
    </Nodes>
    <Edges>
      <Edge From="0" To="1" Label="Source1" />
      <Edge From="1" To="2" Label="Source1" />
    </Edges>
  </Workflow>
</WorkflowBuilder>

[PiezaKake]

Thanks, this worked great!