Difference between revisions of "NumericalTolerance"
(New page: <h2>Numerical Tolerance in Problems: PG Code Snippet</h2> <p style="background-color:#eeeeee;border:black solid 1px;padding:3px;"> <em>This code snippet shows the essential PG code to spe...) |
(Deprecate the problem and add a link to a newer version.) |
||
(7 intermediate revisions by 5 users not shown) | |||
Line 1: | Line 1: | ||
+ | {{historical}} |
||
+ | |||
+ | <p style="font-size: 120%;font-weight:bold">This problem has been replaced with [https://openwebwork.github.io/pg-docs/sample-problems/problem-techniques/NumericalTolerance.html a newer version of this problem]</p> |
||
+ | |||
<h2>Numerical Tolerance in Problems: PG Code Snippet</h2> |
<h2>Numerical Tolerance in Problems: PG Code Snippet</h2> |
||
Line 13: | Line 17: | ||
<table cellspacing="0" cellpadding="2" border="0"> |
<table cellspacing="0" cellpadding="2" border="0"> |
||
<tr valign="top"> |
<tr valign="top"> |
||
− | <th> |
+ | <th>PG problem file</th> |
− | <th> |
+ | <th>Explanation</th> |
</tr> |
</tr> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
<tr valign="top"> |
<tr valign="top"> |
||
<td style="background-color:#ffffdd;border:black 1px dashed;"> |
<td style="background-color:#ffffdd;border:black 1px dashed;"> |
||
<pre> |
<pre> |
||
− | + | Context("Numeric"); |
|
− | + | Context()->flags->set( |
|
tolerance => 0.0001, |
tolerance => 0.0001, |
||
− | tolType => "absolute" |
+ | tolType => "absolute", |
− | + | ); |
|
− | + | $ans = Compute(1.5708); |
|
</pre> |
</pre> |
||
</td> |
</td> |
||
+ | <!-------------------------------------------> |
||
<td style="background-color:#ffffcc;padding:7px;"> |
<td style="background-color:#ffffcc;padding:7px;"> |
||
<p> |
<p> |
||
Line 39: | Line 47: | ||
</p> |
</p> |
||
<pre> |
<pre> |
||
− | + | $ans = Compute(1.5708)->with( |
|
− | tolType=>'absolute', |
+ | tolType => 'absolute', |
+ | tolerance => .0001, |
||
+ | ); |
||
</pre> |
</pre> |
||
</td> |
</td> |
||
</tr> |
</tr> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
<tr valign="top"> |
<tr valign="top"> |
||
<td style="background-color:#ffdddd;border:black 1px dashed;"> |
<td style="background-color:#ffdddd;border:black 1px dashed;"> |
||
<pre> |
<pre> |
||
− | + | BEGIN_TEXT |
|
− | + | Enter \(\frac{\pi}{2}\): \{ans_rule(8)\} |
|
− | + | $BR |
|
− | + | ${BITALIC}(Enter your answer accurate to four |
|
− | + | decimal places.)$EITALIC |
|
− | + | END_TEXT |
|
</pre> |
</pre> |
||
+ | </td> |
||
+ | <!-------------------------------------------> |
||
<td style="background-color:#ffcccc;padding:7px;"> |
<td style="background-color:#ffcccc;padding:7px;"> |
||
<p> |
<p> |
||
Line 60: | Line 73: | ||
</td> |
</td> |
||
</tr> |
</tr> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
<tr valign="top"> |
<tr valign="top"> |
||
<td style="background-color:#eeddff;border:black 1px dashed;"> |
<td style="background-color:#eeddff;border:black 1px dashed;"> |
||
<pre> |
<pre> |
||
− | + | ANS( $ans->cmp() ); |
|
</pre> |
</pre> |
||
+ | </td> |
||
+ | <!-------------------------------------------> |
||
<td style="background-color:#eeccff;padding:7px;"> |
<td style="background-color:#eeccff;padding:7px;"> |
||
<p> |
<p> |
||
− | And we check the answer as we expect. |
||
+ | And we check the answer as we expect. Alternatively, it is possible to specify the tolerance parameters as arguments to <code>cmp()</code> as follows. In this case it is not necessary to specify the tolerance in the Context or when defining the MathObject. |
||
+ | <pre> |
||
+ | ANS($ans->cmp( |
||
+ | tolType => 'absolute', |
||
+ | tolerance => .0001, |
||
+ | )); |
||
+ | </pre> |
||
</p> |
</p> |
||
</td> |
</td> |
||
</tr> |
</tr> |
||
− | </table> |
||
+ | <!--===============================--> |
||
+ | |||
+ | </table> |
||
<p> |
<p> |
||
With old-style answer evaluators: |
With old-style answer evaluators: |
||
Line 79: | Line 105: | ||
<table cellspacing="0" cellpadding="2" border="0"> |
<table cellspacing="0" cellpadding="2" border="0"> |
||
<tr valign="top"> |
<tr valign="top"> |
||
− | <th> |
+ | <th>PG problem file</th> |
− | <th> |
+ | <th>Explanation</th> |
</tr> |
</tr> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
<tr valign="top"> |
<tr valign="top"> |
||
<td style="background-color:#ffffdd;border:black 1px dashed;"> |
<td style="background-color:#ffffdd;border:black 1px dashed;"> |
||
Line 88: | Line 117: | ||
</pre> |
</pre> |
||
</td> |
</td> |
||
+ | <!-------------------------------------------> |
||
<td style="background-color:#ffffcc;padding:7px;"> |
<td style="background-color:#ffffcc;padding:7px;"> |
||
<p> |
<p> |
||
Line 93: | Line 123: | ||
</p> |
</p> |
||
</td> |
</td> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
</tr> |
</tr> |
||
<tr valign="top"> |
<tr valign="top"> |
||
Line 104: | Line 137: | ||
END_TEXT |
END_TEXT |
||
</pre> |
</pre> |
||
+ | </td> |
||
+ | <!-------------------------------------------> |
||
<td style="background-color:#ffcccc;padding:7px;"> |
<td style="background-color:#ffcccc;padding:7px;"> |
||
<p> |
<p> |
||
Line 110: | Line 145: | ||
</td> |
</td> |
||
</tr> |
</tr> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
<tr valign="top"> |
<tr valign="top"> |
||
<td style="background-color:#eeddff;border:black 1px dashed;"> |
<td style="background-color:#eeddff;border:black 1px dashed;"> |
||
<pre> |
<pre> |
||
− | + | ANS(num_cmp($ans, |
|
− | + | tol => 0.0001, |
|
+ | tolType => "absolute", |
||
+ | )); |
||
</pre> |
</pre> |
||
+ | </td> |
||
+ | <!-------------------------------------------> |
||
<td style="background-color:#eeccff;padding:7px;"> |
<td style="background-color:#eeccff;padding:7px;"> |
||
<p> |
<p> |
||
− | And we check the answer, specifying the tolerances we intend in the answer evaluator. The <code>tol</code> and <code>tolType</code> flags behave the same as in the |
+ | And we check the answer, specifying the tolerances we intend in the answer evaluator. The <code>tol</code> and <code>tolType</code> flags behave the same as in the MathObjects version of the problem. |
</p> |
</p> |
||
</td> |
</td> |
||
</tr> |
</tr> |
||
+ | |||
+ | <!--===============================--> |
||
+ | |||
</table> |
</table> |
||
+ | |||
<p style="text-align:center;"> |
<p style="text-align:center;"> |
||
[[IndexOfProblemTechniques|Problem Techniques Index]] |
[[IndexOfProblemTechniques|Problem Techniques Index]] |
||
</p> |
</p> |
||
+ | |||
+ | [[Category:Problem Techniques]] |
Latest revision as of 16:40, 20 June 2023
This problem has been replaced with a newer version of this problem
Numerical Tolerance in Problems: PG Code Snippet
This code snippet shows the essential PG code to specify a numerical tolerance for student answers to a problem. Note that these are insertions, not a complete PG file. This code will have to be incorporated into the problem file on which you are working.
We can control the numerical tolerance expected of the student with MathObjects, or with old-style answer evaluators. Using MathObjects we can control tolerance by setting a "global" tolerance in the Context, as shown in the example below, or by specifying the tolerance that is used for specific MathObjects, as is indicated in the comments to the right. An example with the old-style evaluators appears below the MathObjects examples.
PG problem file | Explanation |
---|---|
Context("Numeric"); Context()->flags->set( tolerance => 0.0001, tolType => "absolute", ); $ans = Compute(1.5708); |
We need no changes to the tagging and description or initialization sections of the file. In the set-up section, we specify the tolerance flags in the
Thus if the correct answer is 17, a
Note that it is also possible to specify the tolerance for the evaluation in the definition of the answer, thereby setting the tolerance only for comparisons using that object. This is done by omitting the $ans = Compute(1.5708)->with( tolType => 'absolute', tolerance => .0001, ); |
BEGIN_TEXT Enter \(\frac{\pi}{2}\): \{ans_rule(8)\} $BR ${BITALIC}(Enter your answer accurate to four decimal places.)$EITALIC END_TEXT |
The text section of the file is the same as usual. |
ANS( $ans->cmp() ); |
And we check the answer as we expect. Alternatively, it is possible to specify the tolerance parameters as arguments to ANS($ans->cmp( tolType => 'absolute', tolerance => .0001, )); |
With old-style answer evaluators:
PG problem file | Explanation |
---|---|
$ans = "1.5708"; |
We need no changes to the tagging and description or initialization sections of the file. In the set-up section, we can specify the value that we're checking against. |
BEGIN_TEXT Enter \(\frac{\pi}{2}\): \{ans_rule(8)\} $BR ${BITALIC}(Enter your answer accurate to four decimal places.)$EITALIC END_TEXT |
The text section of the file is the same as usual. |
ANS(num_cmp($ans, tol => 0.0001, tolType => "absolute", )); |
And we check the answer, specifying the tolerances we intend in the answer evaluator. The |