# The LearningOnline Network with CAPA
# (Publication Handler
#
# $Id: lonproblemstatistics.pm,v 1.16 2002/08/06 17:38:26 minaeibi Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# /home/httpd/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
# (Navigate problems for statistical reports
# YEAR=2001
# 5/5,7/9,7/25/1,8/11,9/13,9/26,10/5,10/9,10/22,10/26 Behrouz Minaei
# 11/1,11/4,11/16,12/14,12/16,12/18,12/20,12/31 Behrouz Minaei
# YEAR=2002
# 1/22,2/1,2/6,2/25,3/2,3/6,3/17,3/21,3/22,3/26,4/7,5/6 Behrouz Minaei
# 5/12,5/14,5/15,5/19,5/26,7/16,7/25,7/29,8/5 Behrouz Minaei
#
###
package Apache::lonproblemstatistics;
use strict;
use Apache::lonnet();
use Apache::lonhtmlcommon;
use Apache::loncoursedata;
use GDBM_File;
sub BuildProblemStatisticsPage {
my ($cacheDB, $students, $courseID, $c, $r)=@_;
my %cache;
unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER,0640)) {
return '
Unable to tie database.';
}
my $Ptr = '';
$Ptr .= '
'."\n";
$r->print($Result);
$r->rflush();
}
sub CloseTable {
my ($cache,$r)=@_;
if($cache->{'DisplayFormat'} eq 'Display CSV Format') {
return;
}
$r->print("\n".'
'."\n");
$r->rflush();
}
# Create progress
sub Create_PrgWin {
my ($r)=@_;
$r->print(<
popwin=open('','popwin','width=400,height=100');
popwin.document.writeln(''+
'LON-CAPA Statistics'+
'
Computation Progress
'+
''+
'');
popwin.document.close();
ENDPOP
$r->rflush();
}
# update progress
sub Update_PrgWin {
my ($totalStudents,$index,$name,$r)=@_;
$r->print('');
$r->rflush();
}
# close Progress Line
sub Close_PrgWin {
my ($r)=@_;
$r->print('');
$r->rflush();
}
# ------ Dump the Student's DB file and handling the data for statistics table
sub ExtractStudentData {
my ($cache,$name,$list,$Discuss,$r,$discriminant)=@_;
my $totalTries = 0;
my $totalAwarded = 0;
my $spent=0;
my $spent_yes=0;
my $TotDiscuss=0;
my $TotalOpend = 0;
my $ProbSolved = 0;
my $ProbTot = 0;
my $TotFirst = 0;
my $TimeTot = 0;
my $Discussed=0;
my $discrim='';
my $tempSequenceOrder=100;
#$Apache::lonxml::debug=1;
#&Apache::lonhomework::showhash(%$cache);
#$Apache::lonxml::debug=0;
foreach my $sequence (split(':', $cache->{'orderedSequences'})) {
my $tempProblemOrder=100;
if($cache->{'ProblemStatisticsMaps'} ne 'All Maps' &&
$cache->{'ProblemStatisticsMaps'} ne $cache->{$sequence.':title'}) {
next;
}
$tempSequenceOrder++;
foreach my $problemID (split(':', $cache->{$sequence.':problems'})) {
my $problem = $cache->{$problemID.':problem'};
my $LatestVersion = $cache->{$name.':version:'.$problem};
# Output dashes for all the parts of this problem if there
# is no version information about the current problem.
#if(!$LatestVersion) {
# foreach my $part (split(/\:/,$cache->{$sequence.':'.
# $problemID.
# ':parts'})) {
# $codes .= "-,";
# $attempts .= "0,";
# }
# next;
#}
my %partData=undef;
$partData{'count'}=0;
# Initialize part data, display skips correctly
# Skip refers to when a student made no submissions on that
# part/problem.
foreach my $part (split(/\:/,$cache->{$sequence.':'.
$problemID.
':parts'})) {
$tempProblemOrder++;
$partData{'count'}++;
$partData{$part.':order'}=$tempProblemOrder;
$partData{$part.':tries'}=0;
$partData{$part.':code'}='-';
}
# Looping through all the versions of each part, starting with the
# oldest version. Basically, it gets the most recent
# set of grade data for each part.
for(my $Version=1; $Version<=$LatestVersion; $Version++) {
foreach my $part (split(/\:/,$cache->{$sequence.':'.
$problemID.
':parts'})) {
if(!defined($cache->{$name.":$Version:$problem".
":resource.$part.solved"})) {
# No grade for this submission, so skip
next;
}
my $tries=0;
my $time=0;
my $awarded=0;
$Discussed=0;
my $code='-';
$awarded = $cache->{"$name:$Version:$problem:resource.".
"$part.awarded"};
$partData{$part.':awarded'} = ($awarded) ? $awarded : 0;
$totalAwarded += $awarded;
$tries = $cache->{"$name:$Version:$problem".
":resource.$part.tries"};
$partData{$part.':tries'} = ($tries) ? $tries : 0;
$partData{$part.':wrong'} = $partData{$part.':tries'};
$totalTries += $tries;
my $val = $cache->{$name.":$Version:$problem".
":resource.$part.solved"};
if ($val eq 'correct_by_student') {$code = 'C';}
elsif ($val eq 'correct_by_override') {$code = 'O';}
elsif ($val eq 'incorrect_attempted') {$code = 'I';}
elsif ($val eq 'incorrect_by_override'){$code = 'I';}
elsif ($val eq 'excused') {$code = 'x';}
$partData{$part.':code'}=$code;
if($partData{$part.':wrong'} ne 0 &&
($code eq 'C' || $code eq 'O')) {
$partData{$part.':wrong'}--;
}
}
}
# Loop through all the parts for the current problem in the
# correct order and prepare the output
my $partCounter=0;
foreach (split(/\:/,$cache->{$sequence.':'.$problemID.
':parts'})) {
$partCounter++;
my $Yes = 0;
if($partData{$_.':code'} eq 'C' ||
$partData{$_.':code'} eq 'O') {
$Yes=1;
}
my $pOrder=$partData{$_.':order'};
my $ptr = $tempSequenceOrder.':'.$pOrder.':'.$problemID;
if($partData{'count'} > 1) {
$ptr .= "*(part $_)";
}
$discrim .= '&';
my ($pr_no,$dod)=split('&',$ptr);
# my $DoDiff=$DoDiff->{$dod};
# $r->print(' '.$name.'---'.$ptr.'==='.$DoDiff);
my $Fac = ($partData{$_.':tries'}) ?
($partData{$_.':awarded'}/$partData{$_.':tries'}) : 0;
my $DisF;
if($Fac > 0 && $Fac < 1) {
$DisF = sprintf( "%.4f", $Fac );
} else {
$DisF = $Fac;
}
if ($Discuss->{"$name:$problem"}) {
$TotDiscuss++;
$Discussed=1;
}
my $time = $cache->{"$name:$LatestVersion:$problem:timestamp"};
$discrim .= $tempSequenceOrder.'@'.$pOrder.'='.$DisF.'+'.$Yes;
$ptr .= '&'.$partData{$_.':tries'}.
'&'.$partData{$_.':wrong'}.
'&'.$partData{$_.':code'};
push (@$list, $ptr."&$Discussed");
# $r->print(' '.$_.$name.'---'.$ptr);
#### if ($DoDiff>0.85) {
$TimeTot += $time;
if ($Yes==1 && $partData{$_.':tries'}==1) {
$TotFirst++;
}
# my $Acts= $Activity->{$name.':'.$problem};
# if ($Acts) {
# my $Pt=&ProcAct( $Acts, $time );
#my ($spe,$beg) = split(/\+/,$Pt);
# my $spe= $Pt;
# if ($Yes==1) {$spent_yes += $spe;}
# $spent += $spe;
#$Beg += $beg;
# $r->print(' '.$name.'---'.$problem.'---'.$spe);
# }
$TotalOpend++;
$ProbTot++;
$tempProblemOrder++;
}
}
}
my $pstr;
if($totalTries) {
my $DisFac = ($totalAwarded/$totalTries);
my $DisFactor = sprintf( "%.4f", $DisFac );
my $TS = sprintf( "%.2f", $spent );
my $TS_yes = sprintf( "%.2f", $spent_yes );
$pstr=$DisFactor.':'.$name.':'.$ProbTot.':'.$TotalOpend.':'.
$totalTries.':'.$ProbSolved.':'.$TotFirst.':'.
$TS_yes.':'.$TS.':'.$TotDiscuss;
(%$discriminant)->{$pstr}=$discrim;
}
}
sub NumericSort {
$a <=> $b;
}
sub OrderedSort {
if ($ENV{'form.order'} eq 'Descending') {
$b <=> $a;
} else {
$a <=> $b;
}
}
sub BuildStatisticsTable {
my ($cache,$upper,$lower,$list,$headings,$students,$r,$color)=@_;
my $NoElements = scalar @$list;
my @list=sort(@$list);
#6666666
# my $file="/home/httpd/perl/tmp/183d.txt";
# open(OUT, ">$file");
#6666666
## &Apache::lonstatistics::Create_PrgWin($r);
##777777
## my (%Activity) = &LoadActivityLog();
## $r->print('');
## my ($doDiffFile) = &LoadDoDiffFile();
##777777
## $Str .= &Classify($discriminantFactor, $students);
my $p_count = 0;
my $dummy;
my $p_val;
my $ResId;
my %TempCache;
my $cIdx=0;
foreach my $sequence (split(':', $cache->{'orderedSequences'})) {
if($cache->{'ProblemStatisticsMaps'} ne 'All Maps' &&
$cache->{'ProblemStatisticsMaps'} ne $cache->{$sequence.':title'}) {
next;
}
&CreateProblemStatisticsTableHeading($cache->{'DisplayFormat'},
$cache->{$sequence.':source'},
$cache->{$sequence.':title'},
$headings,$r);
my ($tar,$Tries,$Wrongs,$Code,$Disc)=split(/\&/,
$list[$cIdx]);
my ($SqOrd,$PrOrd,$Prob)=split(/\:/,$tar);
$sequence+=100;
while ($SqOrd==$sequence && $cIdx<$NoElements) {
my %storestats=();
my $pOrd=$PrOrd;
my $Temp = $Prob;
my $MxTries = 0;
my $TotalTries = 0;
my $YES = 0;
my $Incorrect = 0;
my $Override = 0;
my $StdNo = 0;
my $DiscNo=0;
my @StdLst;
while ($pOrd==$PrOrd && $cIdx<$NoElements)
{
$cIdx++;
$StdNo++;
$StdLst[ $StdNo ] = $Tries;
$TotalTries += $Tries;
if ( $MxTries < $Tries ) { $MxTries = $Tries; }
if ( $Code eq 'C' ){ $YES++; }
elsif( $Code eq 'I' ) { $Incorrect++; }
elsif( $Code eq 'O' ) { $Override++; }
elsif( $Code eq '-' ) { $StdNo--; }
($tar,$Tries,$Wrongs,$Code,$Disc)=split(/\&/,
$list[$cIdx]);
($SqOrd,$PrOrd,$Prob)=split(/\:/,$tar);
}
$p_count++;
my $Dummy;
($ResId,$Dummy)=split(/\*/,$Temp);
$Temp = ''.$cache->{$ResId.':title'}.$Dummy.'';
# my $urlres = $cache->{$sequence.':source'});
#check with Gerd
#symb of the problem (already decluttered and cleaned)
my $urlres = $cache->{$ResId.':problem'};
#------------------------ Compute the Average of Tries about one problem
my $Average = ($StdNo) ? $TotalTries/$StdNo : 0;
$storestats{$ENV{'request.course.id'}.'___'.$urlres.'___timestamp'}=time;
$storestats{$ENV{'request.course.id'}.'___'.$urlres.'___stdno'}=$StdNo;
$storestats{$ENV{'request.course.id'}.'___'.$urlres.'___avetries'}=$Average;
#-------------------------------- Compute percentage of Wrong tries
my $Wrong = ( $StdNo ) ? 100 * ( $Incorrect / $StdNo ) : 0;
#-------------------------------- Compute Standard Deviation
my $StdDev = 0;
if ( $StdNo > 1 ) {
for ( my $n = 0; $n < $StdNo; $n++ ) {
my $Dif = $StdLst[ $n ]-$Average;
$StdDev += $Dif*$Dif;
}
$StdDev /= ( $StdNo - 1 );
$StdDev = sqrt( $StdDev );
}
#-------------------------------- Compute Degree of Difficulty
my $DoDiff = 0;
if( $TotalTries > 0 ) {
$DoDiff = 1 - ( ( $YES + $Override ) / $TotalTries );
# $DoDiff = ($TotalTries)/($YES + $Override+ 0.1);
}
$storestats{$ENV{'request.course.id'}.'___'.$urlres.'___difficulty'}=$DoDiff;
#-------------------------------- Compute the Skewness
my $Skewness = 0;
my $Sum = 0;
if ( $StdNo > 0 && $StdDev > 0 ) {
for ( my $n = 0; $n < $StdNo; $n++ ) {
my $Dif = $StdLst[ $n ]-$Average;
$Skewness += $Dif*$Dif*$Dif;
}
$Skewness /= $StdNo;
$Skewness /= $StdDev*$StdDev*$StdDev;
}
#--------------------- Compute the Discrimination Factors
my ($Up1,$Up2)=split(/\:/,$upper->{$sequence.'@'.$pOrd});
my ($Lw1,$Lw2)=split(/\:/,$lower->{$sequence.'@'.$pOrd});
my $Dis1 = $Up1 - $Lw1;
my $Dis2 = $Up2 - $Lw2;
my $_D1 = sprintf("%.2f", $Dis1);
my $_D2 = sprintf("%.2f", $Dis2);
#----------------- Some restition in presenting the float numbers
my $Avg = sprintf( "%.2f", $Average );
my $Wrng = sprintf( "%.1f", $Wrong );
my $SD = sprintf( "%.1f", $StdDev );
my $DoD = sprintf( "%.2f", $DoDiff );
my $Sk = sprintf( "%.1f", $Skewness );
my $join = $sequence.'@'.$pOrd.'&'.$Temp.'&'.$StdNo.'&'.
$TotalTries.'&'.$MxTries.'&'.$Avg.'&'.
$YES.'&'.$Override.'&'.$Wrng.'&'.$DoD.'&'.
$SD.'&'.$Sk.'&'.$_D1.'&'.$_D2.'&'.
$DiscNo.'&'.$Prob;
$TempCache{'CacheTable:'.($p_count-1)}=$join;
#6666666
# $r->print(' '.$out.'&'.$DoD);
# print (OUT $out.'@'.$DoD.'&');
#6666666
#check with Gerd
$urlres=~/^(\w+)\/(\w+)/;
if ($StdNo) {
&Apache::lonnet::put('resevaldata',\%storestats,$1,$2);
}
#-------------------------------- Row of statistical table
&TableRow($cache,$join,$cIdx,($p_count-1),$r,$color,
\%TempCache);
}
$TempCache{'ProblemCount'}=$p_count;
&CloseTable($cache,$r);
}
### &Close_PrgWin();
#6666666
# close( OUT );
#666666
return \%TempCache;
}
sub CacheStatisticsTable {
my ($state,$cache,$headings,$r,$color)=@_;
my @list = ();
my %TempCache;
my %myHeader = reverse( %$headings );
my $pos = $myHeader{$state};
if ($pos > 0) {$pos++;}
my $p_count = $cache->{'ProblemCount'};
for ( my $k=0; $k<$p_count;$k++) {
my $key=$cache->{'CacheTable:'.$k};
my @Temp=split(/\&/,$key);
$list[$k]=$Temp[$pos].'+'.$key;
}
if ($pos>0) {
@list = sort OrderedSort (@list);
} else {
@list = sort (@list);
}
my $cIdx=0;
if ( $pos == 0 ) {
foreach my $sequence (split(':', $cache->{'orderedSequences'})) {
if($cache->{'ProblemStatisticsMaps'} ne 'All Maps' &&
$cache->{'ProblemStatisticsMaps'} ne $cache->{$sequence.':title'}) {
next;
}
if ($cIdx==$p_count) {
return \%TempCache;
}
&CreateProblemStatisticsTableHeading($cache->{'DisplayFormat'},
$cache->{$sequence.':source'},
$cache->{$sequence.':title'},
$headings,$r);
my ($tar)=split(/\&/,$list[$cIdx]);
$tar=~s/\+//eg;
my ($SqOrd)=split(/\@/,$tar);
$sequence+=100;
while ($SqOrd==$sequence && $cIdx<$p_count) {
my($Pre, $Post) = split(/\+/,$list[$cIdx]);
&TableRow($cache,$Post,$cIdx,$cIdx,$r,$color,\%TempCache);
$cIdx++;
my ($tar)=split(/\&/,$list[$cIdx]);
$tar=~s/\+//eg;
($SqOrd)=split(/\@/,$tar);
}
&CloseTable($cache,$r);
}
}
else {
&CreateProblemStatisticsTableHeading($cache->{'DisplayFormat'},
'Sorted by: ',
$headings->{$pos-1},
$headings,$r);
for ( my $nIndex = 0; $nIndex < $p_count; $nIndex++ ) {
my($Pre, $Post) = split(/\+/,$list[$nIndex]);
&TableRow($cache,$Post,$nIndex,$nIndex,$r,$color,\%TempCache);
}
&CloseTable($cache,$r);
}
return \%TempCache;
}
sub TableRow {
my ($cache,$Str,$Idx,$RealIdx,$r,$color,$GraphDat)=@_;
my($PrOrd,$Temp,$StdNo,$TotalTries,$MxTries,$Avg,$YES,$Override,
$Wrng,$DoD,$SD,$Sk,$_D1,$_D2,$DiscNo,$Prob)=split(/\&/,$Str);
my $Ptr;
if($cache->{'DisplayFormat'} eq 'Display CSV Format') {
my ($ResId,$Dummy)=split(/\*/,$Prob);
$Ptr="\n".' '.
"\n".'"'.($RealIdx+1).'",'.
"\n".'"'.$cache->{$ResId.':title'}.$Dummy.'",'.
"\n".'"'.$cache->{$ResId.':source'}.'",'.
"\n".'"'.$StdNo.'",'.
"\n".'"'.$TotalTries.'",'.
"\n".'"'.$MxTries.'",'.
"\n".'"'.$Avg.'",'.
"\n".'"'.$YES.'",'.
"\n".'"'.$Override.'",'.
"\n".'"'.$Wrng.'",'.
"\n".'"'.$DoD.'",'.
"\n".'"'.$SD.'",'.
"\n".'"'.$Sk.'",'.
"\n".'"'.$_D1.'",'.
"\n".'"'.$_D2.'"'.
"\n".'"'.$DiscNo.'"';
$r->print("\n".$Ptr);
} else {
$Ptr="\n".'
'.
"\n".'
'.($RealIdx+1).'
'.
"\n".'
'.$Temp.'
'.
"\n".'
'.$StdNo.'
'.
"\n".'
'.$TotalTries.'
'.
"\n".'
'.$MxTries.'
'.
"\n".'
'.$Avg.'
'.
"\n".'
'.$YES.'
'.
"\n".'
'.$Override.'
'.
"\n".'
'.$Wrng.'
'.
"\n".'
'.$DoD.'
'.
"\n".'
'.$SD.'
'.
"\n".'
'.$Sk.'
'.
"\n".'
'.$_D1.'
'.
"\n".'
'.$_D2.'
'.
"\n".'
'.$DiscNo.'
';
$r->print("\n".$Ptr.'
' );
}
$GraphDat->{'GraphGif:'.$RealIdx}=$DoD.':'.$Wrng;
}
# For loading the colored table for display or un-colored for print
sub setbgcolor {
my $PrintTable=shift;
my %color;
if ($PrintTable){
$color{"gb"}="#FFFFFF";
$color{"red"}="#FFFFFF";
$color{"yellow"}="#FFFFFF";
$color{"green"}="#FFFFFF";
$color{"purple"}="#FFFFFF";
} else {
$color{"gb"}="#DDFFFF";
$color{"red"}="#FFDDDD";
$color{"yellow"}="#EEFFCC";
$color{"green"}="#DDFFDD";
$color{"purple"}="#FFDDFF";
}
return \%color;
}
sub ProblemStatisticsButtons {
my ($displayFormat)=@_;
my $Ptr = '
';
$Ptr .= '';
$Ptr .= '
';
$Ptr .= '#Stdnts
';
$Ptr .= '
Total Number of Students opened the problem.';
$Ptr .= '
';
$Ptr .= 'Tries
';
$Ptr .= '
Total Number of Tries for solving the problem.';
$Ptr .= '
';
$Ptr .= 'Mod
';
$Ptr .= '
Maximunm Number of Tries for solving the problem.';
$Ptr .= '
';
$Ptr .= 'Mean
';
$Ptr .= '
Average Number of the tries. [ Tries / #Stdnts ]';
$Ptr .= '
';
$Ptr .= '#YES
';
$Ptr .= '
Number of students solved the problem correctly.';
$Ptr .= '
';
$Ptr .= '#yes
';
$Ptr .= '
Number of students solved the problem by override.';
$Ptr .= '
';
$Ptr .= '%Wrng
';
$Ptr .= '
Percentage of students tried to solve the problem ';
$Ptr .= 'but still incorrect. [ 100*((#Stdnts-(#YES+#yes))/#Stdnts) ]';
$Ptr .= '
';
$Ptr .= 'DoDiff
';
$Ptr .= '
Degree of Difficulty of the problem. ';
$Ptr .= '[ 1 - ((#YES+#yes) / Tries) ]';
$Ptr .= '
';
$Ptr .= 'S.D.
';
$Ptr .= '
Standard Deviation of the tries. ';
$Ptr .= '[ sqrt(sum((Xi - Mean)^2)) / (#Stdnts-1) ';
$Ptr .= 'where Xi denotes every student\'s tries ]';
$Ptr .= '
';
$Ptr .= 'Skew.
';
$Ptr .= '
Skewness of the students tries.';
$Ptr .= '[(sqrt( sum((Xi - Mean)^3) / #Stdnts)) / (S.D.^3)]';
$Ptr .= '
';
$Ptr .= 'Dis.F.
';
$Ptr .= '
Discrimination Factor: A Standard for evaluating the ';
$Ptr .= 'problem according to a Criterion ';
$Ptr .= '[Applied Criterion in %27 Upper Students - ';
$Ptr .= 'Applied the same Criterion in %27 Lower Students] ';
$Ptr .= '1st Criterion for Sorting the Students: ';
$Ptr .= 'Sum of Partial Credit Awarded / Total Number of Tries ';
$Ptr .= '2nd Criterion for Sorting the Students: ';
$Ptr .= 'Total number of Correct Answers / Total Number of Tries';
$Ptr .= '
';
$Ptr .= '
Disc.
';
$Ptr .= '
Number of Students had at least one discussion.';
$Ptr .= '
';
return $Ptr;
}
#------- Processing upperlist and lowerlist according to each problem
sub ProcessDiscriminant {
my ($List,$r) = @_;
my @sortedList = sort (@$List);
my $Count = scalar @sortedList;
my $Problem;
my @Dis;
my $Slvd=0;
my $tmp;
my $Sum1=0;
my $Sum2=0;
my $nIndex=0;
my $nStudent=0;
my %Proc=undef;
while ($nIndex<$Count) {
# $r->print(" $nIndex) $sortedList[$nIndex]");
($Problem,$tmp)=split(/\=/,$sortedList[$nIndex]);
@Dis=split(/\+/,$tmp);
my $Temp = $Problem;
do {
$nIndex++;
$nStudent++;
$Sum1 += $Dis[0];
$Sum2 += $Dis[1];
($Problem,$tmp)=split(/\=/,$sortedList[$nIndex]);
@Dis=split(/\+/,$tmp);
} while ( $Problem eq $Temp && $nIndex < $Count );
$Proc{$Temp}=($Sum1/$nStudent).':'.($Sum2/$nStudent);
# $r->print(" $nIndex) $Temp --> ($nStudent) $Proc{$Temp}");
$Sum1=0;
$Sum2=0;
$nStudent=0;
}
return %Proc;
}
#------- Creating Discimination factor
sub Discriminant {
my ($discriminant,$r)=@_;
my @discriminantKeys=keys(%$discriminant);
my $Count = scalar @discriminantKeys;
my $UpCnt = int(0.27*$Count);
my $low=0;
my $up=$Count-$UpCnt;
my @UpList=();
my @LowList=();
$Count=0;
foreach my $key (sort(@discriminantKeys)) {
$Count++;
if($low < $UpCnt || $Count > $up) {
$low++;
my $str=$discriminant->{$key};
foreach(split(/\&/,$str)){
if($_) {
if($low<$UpCnt) { push(@LowList,$_); }
else { push(@UpList,$_); }
}
}
}
}
my %DisUp = &ProcessDiscriminant(\@UpList,$r);
my %DisLow = &ProcessDiscriminant(\@LowList,$r);
return (\%DisUp, \%DisLow);
}
#---- END Problem Statistics Web Page ----------------------------------------
#---- Problem Statistics Graph Web Page --------------------------------------
# ------------------------------------------- Prepare data for Graphical chart
sub BuildGraphicChart {
my ($ylab,$r,$cacheDB)=@_;
my %cache;
my $Col;
my $data='';
my $count = 0;
my $Max = 0;
unless(tie(%cache,'GDBM_File',$cacheDB,&GDBM_READER,0640)) {
return 'Unable to tie database.';
}
my $p_count = $cache{'ProblemCount'};
for ( my $k=0; $k<$p_count;$k++) {
my @Temp=split(/\:/,$cache{'GraphGif:'.$k});
my $inf = $Temp[$Col];
if ( $Max < $inf ) {$Max = $inf;}
$data .= $inf.',';
$count++;
}
untie(%cache);
# $r->print(" count=$p_count >>data= $data");
if ( $Max > 1 ) {
$Max += (10 - $Max % 10);
$Max = int($Max);
} else { $Max = 1; }
my $cid=$ENV{'request.course.id'};
if ( $ylab eq 'DoDiff Graph' ) {
$ylab = 'Degree-of-Difficulty';
$Col = 0;
} else {
$ylab = 'Wrong-Percentage';
$Col = 1;
}
my $Course = $ENV{'course.'.$cid.'.description'};
$Course =~ s/\ /"_"/eg;
my $GData=$Course.'&'.'Problems#'.'&'.$ylab.'&'.
$Max.'&'.$count.'&'.$data;
$r->print('');
return;
}
1;
__END__