--- loncom/interface/statistics/lonstathelpers.pm 2004/02/13 18:34:40 1.3 +++ loncom/interface/statistics/lonstathelpers.pm 2004/02/19 20:17:01 1.4 @@ -1,6 +1,6 @@ # The LearningOnline Network with CAPA # -# $Id: lonstathelpers.pm,v 1.3 2004/02/13 18:34:40 matthew Exp $ +# $Id: lonstathelpers.pm,v 1.4 2004/02/19 20:17:01 matthew Exp $ # # Copyright Michigan State University Board of Trustees # @@ -337,6 +337,322 @@ sub get_prev_curr_next { return ($prev,$curr,$next); } + +##################################################### +##################################################### + +=pod + +=item analyze_problem_as_student + +Analyzes a homework problem for a student and returns the correct answer +for the student. Attempts to put together an answer for problem types +that do not natively support it. + +Inputs: $resource: a resource object + $sname, $sdom, $partid, $respid + +Returns: $answer + +=cut + +##################################################### +##################################################### +sub analyze_problem_as_student { + my ($resource,$sname,$sdom,$partid,$respid) = @_; + my $returnvalue; + my $url = $resource->{'src'}; + my $symb = $resource->{'symb'}; + my $courseid = $ENV{'request.course.id'}; + my $Answ=&Apache::lonnet::ssi($url,('grade_target' => 'analyze', + 'grade_domain' => $sdom, + 'grade_username' => $sname, + 'grade_symb' => $symb, + 'grade_courseid' => $courseid)); + (my $garbage,$Answ)=split(/_HASH_REF__/,$Answ,2); + my %Answer=&Apache::lonnet::str2hash($Answ); + my $prefix = $partid.'.'.$respid; + my $key = $prefix.'.answer'; + if (exists($Answer{$key})) { + my $student_answer = $Answer{$key}->[0]; + if (! defined($student_answer)) { + $student_answer = $Answer{$key}->[1]; + } + $returnvalue = $student_answer; + } else { + if (exists($Answer{$prefix.'.shown'})) { + # The response has foils + my %values; + while (my ($k,$v) = each(%Answer)) { + next if ($k !~ /^$prefix\.foil\.(value|area)\.(.*)$/); + my $foilname = $2; + $values{$foilname}=$v; + } + foreach my $foil (@{$Answer{$prefix.'.shown'}}) { + if (ref($values{$foil}) eq 'ARRAY') { + $returnvalue.=&HTML::Entities::encode($foil).'='. + join(',',map {&HTML::Entities::encode($_)} @{$values{$foil}}).'&'; + } else { + $returnvalue.=&HTML::Entities::encode($foil).'='. + &HTML::Entities::encode($values{$foil}).'&'; + } + } + $returnvalue =~ s/ /\%20/g; + chop ($returnvalue); + } + } + return $returnvalue; +} + + +## +## The following is copied from datecalc1.pl, part of the +## Spreadsheet::WriteExcel CPAN module. +## +## +###################################################################### +# +# Demonstration of writing date/time cells to Excel spreadsheets, +# using UNIX/Perl time as source of date/time. +# +# Copyright 2000, Andrew Benham, adsb@bigfoot.com +# +###################################################################### +# +# UNIX/Perl time is the time since the Epoch (00:00:00 GMT, 1 Jan 1970) +# measured in seconds. +# +# An Excel file can use exactly one of two different date/time systems. +# In these systems, a floating point number represents the number of days +# (and fractional parts of the day) since a start point. The floating point +# number is referred to as a 'serial'. +# The two systems ('1900' and '1904') use different starting points: +# '1900'; '1.00' is 1 Jan 1900 BUT 1900 is erroneously regarded as +# a leap year - see: +# http://support.microsoft.com/support/kb/articles/Q181/3/70.asp +# for the excuse^H^H^H^H^H^Hreason. +# '1904'; '1.00' is 2 Jan 1904. +# +# The '1904' system is the default for Apple Macs. Windows versions of +# Excel have the option to use the '1904' system. +# +# Note that Visual Basic's "DateSerial" function does NOT erroneously +# regard 1900 as a leap year, and thus its serials do not agree with +# the 1900 serials of Excel for dates before 1 Mar 1900. +# +# Note that StarOffice (at least at version 5.2) does NOT erroneously +# regard 1900 as a leap year, and thus its serials do not agree with +# the 1900 serials of Excel for dates before 1 Mar 1900. +# +###################################################################### +# +# Calculation description +# ======================= +# +# 1900 system +# ----------- +# Unix time is '0' at 00:00:00 GMT 1 Jan 1970, i.e. 70 years after 1 Jan 1900. +# Of those 70 years, 17 (1904,08,12,16,20,24,28,32,36,40,44,48,52,56,60,64,68) +# were leap years with an extra day. +# Thus there were 17 + 70*365 days = 25567 days between 1 Jan 1900 and +# 1 Jan 1970. +# In the 1900 system, '1' is 1 Jan 1900, but as 1900 was not a leap year +# 1 Jan 1900 should really be '2', so 1 Jan 1970 is '25569'. +# +# 1904 system +# ----------- +# Unix time is '0' at 00:00:00 GMT 1 Jan 1970, i.e. 66 years after 1 Jan 1904. +# Of those 66 years, 17 (1904,08,12,16,20,24,28,32,36,40,44,48,52,56,60,64,68) +# were leap years with an extra day. +# Thus there were 17 + 66*365 days = 24107 days between 1 Jan 1904 and +# 1 Jan 1970. +# In the 1904 system, 2 Jan 1904 being '1', 1 Jan 1970 is '24107'. +# +###################################################################### +# +# Copyright (c) 2000, Andrew Benham. +# This program is free software. It may be used, redistributed and/or +# modified under the same terms as Perl itself. +# +# Andrew Benham, adsb@bigfoot.com +# London, United Kingdom +# 11 Nov 2000 +# +###################################################################### +#----------------------------------------------------------- +# calc_serial() +# +# Called with (up to) 2 parameters. +# 1. Unix timestamp. If omitted, uses current time. +# 2. GMT flag. Set to '1' to return serial in GMT. +# If omitted, returns serial in appropriate timezone. +# +# Returns date/time serial according to $DATE_SYSTEM selected +#----------------------------------------------------------- +sub calc_serial { + # Use 1900 date system on all platforms other than Apple Mac (for which + # use 1904 date system). + my $DATE_SYSTEM = ($^O eq 'MacOS') ? 1 : 0; + my $time = (defined $_[0]) ? $_[0] : time(); + my $gmtflag = (defined $_[1]) ? $_[1] : 0; + # + # Divide timestamp by number of seconds in a day. + # This gives a date serial with '0' on 1 Jan 1970. + my $serial = $time / 86400; + # + # Adjust the date serial by the offset appropriate to the + # currently selected system (1900/1904). + if ($DATE_SYSTEM == 0) { # use 1900 system + $serial += 25569; + } else { # use 1904 system + $serial += 24107; + } + # + unless ($gmtflag) { + # Now have a 'raw' serial with the right offset. But this + # gives a serial in GMT, which is false unless the timezone + # is GMT. We need to adjust the serial by the appropriate + # timezone offset. + # Calculate the appropriate timezone offset by seeing what + # the differences between localtime and gmtime for the given + # time are. + # + my @gmtime = gmtime($time); + my @ltime = localtime($time); + # + # For the first 7 elements of the two arrays, adjust the + # date serial where the elements differ. + for (0 .. 6) { + my $diff = $ltime[$_] - $gmtime[$_]; + if ($diff) { + $serial += _adjustment($diff,$_); + } + } + } + # + # Perpetuate the error that 1900 was a leap year by decrementing + # the serial if we're using the 1900 system and the date is prior to + # 1 Mar 1900. This has the effect of making serial value '60' + # 29 Feb 1900. + # + # This fix only has any effect if UNIX/Perl time on the platform + # can represent 1900. Many can't. + # + unless ($DATE_SYSTEM) { + $serial-- if ($serial < 61); # '61' is 1 Mar 1900 + } + return $serial; +} + +sub _adjustment { + # Based on the difference in the localtime/gmtime array elements + # number, return the adjustment required to the serial. + # + # We only look at some elements of the localtime/gmtime arrays: + # seconds unlikely to be different as all known timezones + # have an offset of integral multiples of 15 minutes, + # but it's easy to do. + # minutes will be different for timezone offsets which are + # not an exact number of hours. + # hours very likely to be different. + # weekday will differ when localtime/gmtime difference + # straddles midnight. + # + # Assume that difference between localtime and gmtime is less than + # 5 days, then don't have to do maths for day of month, month number, + # year number, etc... + # + my ($delta,$element) = @_; + my $adjust = 0; + # + if ($element == 0) { # Seconds + $adjust = $delta/86400; # 60 * 60 * 24 + } elsif ($element == 1) { # Minutes + $adjust = $delta/1440; # 60 * 24 + } elsif ($element == 2) { # Hours + $adjust = $delta/24; # 24 + } elsif ($element == 6) { # Day of week number + # Catch difference straddling Sat/Sun in either direction + $delta += 7 if ($delta < -4); + $delta -= 7 if ($delta > 4); + # + $adjust = $delta; + } + return $adjust; +} + +########################################################### +########################################################### + +=pod + +=item get_problem_data + +Returns a data structure describing the problem. + +Inputs: $url + +Returns: %Partdata + +=cut + +## note: we must force each foil and option to not begin or end with +## spaces as they are stored without such data. +## +########################################################### +########################################################### +sub get_problem_data { + my ($url) = @_; + my $Answ=&Apache::lonnet::ssi($url,('grade_target' => 'analyze')); + (my $garbage,$Answ)=split(/_HASH_REF__/,$Answ,2); + my %Answer; + %Answer=&Apache::lonnet::str2hash($Answ); + my %Partdata; + foreach my $part (@{$Answer{'parts'}}) { + while (my($key,$value) = each(%Answer)) { + # + # Logging code: + if (1) { + &Apache::lonnet::logthis($part.' got key "'.$key.'"'); + if (ref($value) eq 'ARRAY') { + &Apache::lonnet::logthis(' @'.join(',',@$value)); + } else { + &Apache::lonnet::logthis(' '.$value); + } + } + # End of logging code + next if ($key !~ /^$part/); + $key =~ s/^$part\.//; + if (ref($value) eq 'ARRAY') { + if ($key eq 'options') { + $Partdata{$part}->{'_Options'}=$value; + } elsif ($key eq 'concepts') { + $Partdata{$part}->{'_Concepts'}=$value; + } elsif ($key =~ /^concept\.(.*)$/) { + my $concept = $1; + foreach my $foil (@$value) { + $Partdata{$part}->{'_Foils'}->{$foil}->{'_Concept'}= + $concept; + } + } elsif ($key =~ /^(incorrect|answer|ans_low|ans_high)$/) { + $Partdata{$part}->{$key}=$value; + } + } else { + if ($key=~ /^foil\.text\.(.*)$/) { + my $foil = $1; + $Partdata{$part}->{'_Foils'}->{$foil}->{'name'}=$foil; + $value =~ s/(\s*$|^\s*)//g; + $Partdata{$part}->{'_Foils'}->{$foil}->{'text'}=$value; + } elsif ($key =~ /^foil\.value\.(.*)$/) { + my $foil = $1; + $Partdata{$part}->{'_Foils'}->{$foil}->{'value'}=$value; + } + } + } + } + return %Partdata; +} + #################################################### ####################################################