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Annotation of loncom/html/adm/help/tex/Custom_Response_Problems.tex, revision 1.1

1.1     ! www         1: \label{Custom_Response_Problems}
        !             2: Custom Response is a way to have a problem graded based on an algorithm. The use of this response type is
        !             3: generally discouraged, since the responses will not be analyzable by the LON-CAPA statistics tools.
        !             4: 
        !             5: The student answer is stored in the
        !             6: variable \$submission, and needs to be evaluated by Perl code inside the <answer>-tag. Custom Response needs to return a standard LON-CAPA grading code:
        !             7: \begin{itemize}
        !             8: \item EXACT\_ANS: return if solved exactly correctly
        !             9: \item APPROX\_ANS: return if solved approximately
        !            10: \item INCORRECT: return if not correct, loose try
        !            11: \item SIG\_FAIL, NO\_UNIT, ANS\_CNT\_NOT\_MATCH, BAD\_FORMULA, 
        !            12: WANTED\_NUMERIC: return if not correct for different reasons, do not loose try
        !            13: \end{itemize}
        !            14: The answer display is shown instead of the student response in 'show answer' mode.
        !            15: The following example illustrates this:
        !            16: \begin{verbatim}
        !            17: <problem>
        !            18: <startouttext />Accept an answer of around 90 or -90<endouttext />
        !            19:   <customresponse answerdisplay="something near 90 or -90">
        !            20:     <answer type="loncapa/perl">
        !            21: # We do not want a vector
        !            22: if ($submission=~/\,/) { return 'ANS_CNT_NOT_MATCH'; }
        !            23: # Need a numerical answer here
        !            24: if ($submission!~/^[\d\.\-\e]+$/i) { return 'WANTED_NUMERIC'; }
        !            25: $difference=abs(90-abs($submission));
        !            26: if ($difference==0) { return 'EXACT_ANS'; }
        !            27: if ($difference < 0.1) { return 'APPROX_ANS'; }
        !            28: return 'INCORRECT';</answer>
        !            29:     <textline readonly="no" />
        !            30:   </customresponse>
        !            31: </problem>
        !            32: \end{verbatim}