RandadjustIf

Random variables can be adjusted to satisfy a specific constraint.

For example we might adjust the variable x to be always greater than the variable y.

The command \randadjustIf has the syntax \randadjustIf{[varlist]}{[relation]} .

  • varlist comma separated list of variables to be adjusted
  • relation a relation that defines an avoidance condition under which the variables in varlist should be adjusted
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\begin{question}
 
    \begin{variables}
        \randint[Z]{x}{-10}{10}
        \randint[Z]{y}{-10}{10}
        \drawFromSet{a}{1,2,3}
        \drawFromSet{b}{1,2,3}
        \randadjustIf{x,y}{x <= y} %adjust x and y if x is not greater than y
        \randadjustIf{b}{a = b}    %adjust b if b equals a
    \end{variables}
 
\end{question}
\randadjustIf on a variable defined by \drawFromSet only works for (the default) type _number_

calling \randadjustIf multiple times

You may call randadjustIf multiple times to adjust disjoint lists of variables as in the following example:

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\begin{question}
    \begin{variables}
        \randint[Z]{x}{-10}{10}
        \randint[Z]{y}{-10}{10}
        \randint[Z]{c}{-10}{10}
        \randint[Z]{d}{-10}{10}
        \randadjustIf{x,y}{x <= y} %adjust x and y if x is not greater than y
        \randadjustIf{c,d}{c = d OR c = x}
    \end{variables}
 
\end{question}
You should *NEVER* adjust the same variable twice. The following example might lead to problems:
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\begin{question}
 
    \begin{variables}
        \randint[Z]{x}{-10}{10}
        \randint[Z]{y}{-10}{10}
        \randint[Z]{c}{-10}{10}
        \randint[Z]{d}{-10}{10}
        \randadjustIf{x,y}{x <= y} %adjust x and y if x is not greater than y
        \randadjustIf{c,x}{c = d OR c = x} % here the variable x will be re-adjusted
                                           % and the constraint from previous randadjustIf might be broken.
    \end{variables}
 
\end{question}

Adjusting global variables

Just as random variables defined inside the question environment, global variables
(which are defined in the problem environment) can be adjusted, too.

You may use \randadjustIf in the same
manner as explained above, also multiple times for disjoint sets of global variables. You should NOT adjust
global variables within a question, but only in the problem environment where they are defined.

Alternatively use a switch/case statement