Description
These three macros control the type of grading in Numeric questions.Syntax
\digits{sig-digits}
- sig-digits
- The number of significant digits to be considered in grading.
\err{tolerance}
- tolerance
- The (absolute) error allowed in the student's response.
\percenterr{tolerance}
- tolerance
- The percentage error allowed in the student's response.
The types of grading
Exact value
The student's answer must match the value given in the
\answer
field. There is no error
tolerance.
If none of \digits
, \err
, or
\percenterr
are present, the grading type is
set to 'exact value'.
Exact significant digits
The student's answer must agree with the value given in
the \answer
field to a specified number of
significant digits.
To use this grader, use \digits
alone to
specify the required number of significant digits. For
instance, using only \digits{3}
with
\answer{2.5}
allows only
2.50
as a correct response.
Significant digits with tolerance
The student's answer must agree with the value given in
the \answer
field to within a specified
tolerance at a given number of significant digits.
To use this grader, use \digits
to specify
the number of significant digits, together with \err
to
specify the tolerance allowed at that number of digits. For
example, using \err{2}
and
\digits{3}
, with \answer{2.5}
, allows any answer between
2.48
and 2.52
to be accepted
(tolerance of 2 at the third significant digit).
Absolute tolerance
The student's answer must agree with the value given in
the \answer
field to within a specified
(absolute) tolerance.
To use this grader, use \err
alone to set
the allowed tolerance. For example, using \err{0.25}
with \answer{2.5}
allows any response between
2.25
and 2.75
to be accepted.
Relative tolerance
The student's answer must agree with the value given in
the \answer
field to within a specified percent
error.
To use this grader, use \percenterr
to
specify the allowed percentage tolerance. \percenterr
may not be used with either \digits
or
\err
. For example, using \percenterr{5}
with \answer{2.5}
allows any response between 2.5
× 0.95 and 2.5 × 1.05 to be accepted.