How write questions and answers

Type of problem, question and answer

\type{...} can be set for the whole group of questions, but can also be set individually for each question and answer.
The position of the command determines how it works.

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\begin{problem}
  \type{...} % set for all questions
 
  \begin{question}
    \type{...} % or set only for this question and all their answers
 
    \begin{answer}
      \type{...} % or set only for this answer
    \end{answer}         
 
  \end{question}        
\end{problem}

What type is applicable

Type Preview
input.number
?

more
005
input.finite-number-set
?

more
006
input.function
Compare the user's answer numerically
with the pre-given solution

more
007
input.interval
?

more
008
input.cases.function
Designed for case differentiations of e.g. absolute value functions.
Note that you can only use this input type in an answer environment.

more
009
input.matrix
If the solution to a question is a row vector, a columne vector or a matrix,
the generic problem is of the type input.matrix.

more
010
input.text
?

more
011
input.truth-table
?

more
016
mc.matrix
?

more
012
mc.unique
?

more
013
mc.yesno
?

more
014
mc.multiple
?

more
015

Overview input field questions

Number fields

All variables and functions are interpreted in a number field which can be defined by the \field{...} command. It can take one of the following values:

number field Description
real real numbers (i.e. double values); this is the default value if the \field{number field} command is omitted
integer integer numbers
rational rational numbers
complex complex numbers with real numbers as real and imaginary parts
complex-rational complex numbers with rational numbers as real and imaginary parts
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\begin{problem}
  \field{...} % set for all questions
 
  \begin{question}
    \field{...} % or set only for this question and all their answers
 
    \begin{answer}
      \field{...} % or set only for this answer
    \end{answer}         
 
  \end{question}        
\end{problem}

Variables

Questions can become dynamic and personalised through the use of variables and functions. These must be defined
in a variables environment

The environment \begin{variables} ... \end{variables} can be set for the whole group of questions, but can also be
set individually for each question. The position of the command determines how it works.

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\begin{problem}
 
    \begin{variables} % set for all questions
      ...
    \end{variables}
 
    \begin{question}
      \begin{variables} % set only for this questions
        ...
      \end{variables}
 
      \begin{answer}
      \end{answer}         
 
    \end{question}        
\end{problem}

Example

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\begin{question}
   \begin{variables}
       \number{a}{12}
       \number{b}{4}
       \number{c}{10}
       \number{d}{5}
       \function{f}{a/b}
       \function{g}{c/d}
   \end{variables}
   ...
\end{question}

Will result in variables

  • $$a=12$$,
  • $$b=4$$,
  • $$c=10$$,
  • $$d=5$$ and
  • functions $$f=\frac{12}{4}4$$ and $$g=\frac{10}{5}$$

Commands

Command Description Details
\number A fixed number variable, this can be any kind of number. The field command determines how the number will be interpreted.
\function A function definition, the definition may include variables and other functions.
When an included variable is not defined, it will be a free variable.
Again, the field command determines how the numbers within the function will be interpreted.
function
\derivative Creates a new function representing the derivative of the expression/variable that was passed into it. derivative
\substitute Creates a new function that is the composition of two other functions. substitute
\randint A random integer number, including zero (same as randint[z])
\randint[Z] A random integer number, excluding zero Random numbers
\randdouble A random double number, including zero Random numbers
\randrat A random rational number, including zero Random numbers
\drawFromSet Draw randomly a number (or string) from a set Random numbers
\randadjustIf Random variables can be adjusted to satisfy a specific constraint. randadjustIf

Using Variables in text

All variables can be used in texts (e.g. question task, answer text) by using the tex command \var with the name of the variable as argument:

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\begin{question}
 
  \begin{variables}
    \function{f}{a/3}
  \end{variables}
 
  \text{Determine the decimal expansion of $\var{f}$ correct to three decimal places.}
 
  \begin{choice}
    \text{$\var{solution1}$}
  \end{choice}
 
\end{question}

Random numbers

Random numbers can be used instead of fixed numbers to personalize problem data.

Example

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\begin{question}
 
  \begin{variables}
      \randint[Z]{x1}{-10}{10}  %\randint[Z]{name}{min}{max}
      \randdouble{x2}{0}{1}
      \randrat{name}{minNumerator}{maxNumerator}{minDenominator}{maxDenominator}
  \end{variables}
 
\end{question}

\drawFromSet Draw randomly a number (or string) from a set

  • parameters \drawFromSet[options]{name}{set}
  • numbers in the set can be integer, rational or double numbers
  • separator in the set can be any (non white space) character, default separator is the comma
  • type is either number or string, default type is number
  • multiple options are separated by a space (see example below)
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\begin{question}
 
  \begin{variables}
      \drawFromSet{a}{1,2,3,4,5,6}
      \drawFromSet{b}{1/2,5,1.3,9/11,42}
      \drawFromSet[separator=;]{c}{1;2.1;3.5;9}
      \drawFromSet[separator=; type=string]{d}{hello;world}
  \end{variables}
 
\end{question}

Variable pools

Instead of using random values for numbers it is possible to define several sets of values inside a so called variable pool.

  • A pool consists of several variables environments holding each the elements for a single set of variables.
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\begin{question}
 
  \begin{pool}
    \begin{variables}
      \randint{a}{1}{3}
      \drawFromSet{b}{1,2,3}
      \randadjustIf{a,b}{a = b}
      \function[calculate]{f}{2*a+b}
    \end{variables}   
 
    \begin{variables}
      \randint{a}{-3}{-1}
      \drawFromSet{b}{-1,-2,-3}
      \randadjustIf{a,b}{a = b}
      \function[calculate]{f}{2*a-b}
    \end{variables}   
  \end{pool}
 
\end{question}
  • A single set will be chosen randomly for every homework problem. The following example shows a pool with two sets of variables:
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\begin{question}
 
  \begin{pool}
 
      \begin{variables}
          \number{a}{7}
          \number{b}{3}
      \end{variables}
 
      \begin{variables}
          \number{a}{5}
          \number{b}{6}
      \end{variables}
 
  \end{pool}
 
\end{question}
Variable pools can only be used inside a question. There are no global variable pools at the moment.