WOLFRAM SYSTEM MODELER
    firstTrueIndexReturns the index of the first true element of a Boolean vector  | 
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SystemModel["Modelica.Math.BooleanVectors.firstTrueIndex"]

This information is part of the Modelica Standard Library maintained by the Modelica Association.
firstTrueIndex(b);
Returns the index of the first true element of the Boolean vector b. If no element is true or b is an empty vector (i.e., size(b,1)=0) the function returns 0.
  Boolean b1[3] = {false, false, false};
  Boolean b2[3] = {false, true, false};
  Boolean b3[4] = {false, true, false, true};
  Integer r1, r2, r3;
algorithm
  r1 = firstTrueIndex(b1);  // r1 = 0
  r2 = firstTrueIndex(b2);  // r2 = 2
  r3 = firstTrueIndex(b3);  // r3 = 2
allTrue, andTrue, anyTrue, countTrue, enumerate, index, and oneTrue.
| b | 
         Type: Boolean[:] Description: Boolean vector  | 
    
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| index | 
         Type: Integer Description: Index of the first true element of b  | 
    
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