Using Conditional Expressions in Equations

You can specify conditional equations by using if statements.

equations
  [...]
  if Expression
    [...]
  elseif Expression
    [...]
  else
    [...]
  end
  [...]
end

Each [...] section may contain one or more equation expressions.

You can nest if statements, for example:

equations
  [...]
  if Expression
    [...]
    if Expression
       [...]
    else
    [...]
    end
  else
    [...]
  end
  [...]
end

Every if requires an else.
The total number of equation expressions, their dimensionality, and their order must be the same for every branch of the if-elseif-else statement. However, this rule does not apply to the assert expressions, because they are not included in the expression count for the branch.

For a component where x and y are declared as 1x1 variables, specify the following piecewise equation:

$y = {\begin{array}{l} x & for - 1 < = x < = 1 \\ x^{2} & otherwise \end{array}$

This equation, written in the Simscape™ language, would look like:

equations
  if x >= -1 && x <= 1
    y == x;
  else
    y == x^2;
  end
end

Another way to write this equation in the Simscape language is:

equations
  y == if x>=-1 && x<=1, x else x^2 end
end

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