number fields
Number fields
All variables and functions are interpreted in a number field which can be defined within the
question environment by the \field{...}
command. It can take one of the following values:
number field 
Description 
real 
real numbers (i.e. decimal numbers); 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 
complexrational 
complex numbers with rational numbers as real and imaginary parts 
1 2 3 4 5 6 7 8 9 10 11  \begin{problem}
\begin{question}
\field{...} % set for this question and all their answers
\begin{answer}
...
\end{answer}
\end{question}
\end{problem}

Precision of real numbers
If the number field is chosen to be real or complex, there is the issue of precision 
on one hand for displaying the numbers/functions, and on the other for the correction.
The display precision always has to be greater of equal to the corrector precision.
Display precision
For displaying variables defined by \number
,\randdouble
, or \randrat
one uses the
command \displayprecision{\} which defines the number of digits
used for displaying.
If not specified, then the generic problem will use the default value of 2.
When a number was created by the \function
command (or \substitute
or \derivative
)
using the calculate option, the precision defined with the above command will be
ignored. This is because computations should not be rounded while not visible to the user.
In case you do want to display the calculated value then set the precision within the command,
\function[calculate,3]{f}{c/3}
.
Again this value should be $$\geq$$ corrector precision.
Corrector precision
The precision used for correction depends on the type of the answer.
For type input.number, one uses the command
\correctorprecision[correctorOption]{number of decimal digits}
similar to \displayprecision
. For details see the wikipage about rounding
If \correctorprecision
is not specified, then the generic problem will use the default
value of 2.
For answers of type input.function the precision is given as an optional argument in the
command that specifies how to check the given answer for correctness.
See Corrector commands for input.function.