After an update of the Ubuntu distribution running out WeBWorK server, I have encountered the following error for a few of our problems. I have tried making the change to the XMLRPC/Lite.pm file mentioned here to try to deal with a possible issue with UTF-8 to no avail. Does anyone know what might be causing this?

Thanks,

Kyle

## WeBWorK Error

### Error messages

### Error details

```
Problem2
1. ERROR caught by Translator while processing problem file:Library/PCC/BasicMath/MeanMedianMode/MeanMedianMode230.pg
****************
ERRORS from evaluating PG file:
```

Error detected while loading [PG]/macros/contextPercent.pl:
PG_macro_file_eval detected error at line 124 of file [PG]/lib/PGloadfiles.pm
Malformed UTF-8 character (fatal) at line 1 of (eval 8503), chunk 1.
The calling package is PGloadfiles
Died within PGloadfiles::compile_file called at line 172 of [PG]/lib/PGloadfiles.pm
from within PGloadfiles::loadMacros called at line 581 of [PG]/macros/PG.pl
from within main::loadMacros called at line 24 of (eval 8256)

****************

------Input Read
1 # WeBWorK problem written by Carl Yao
2 # Portland Community College
3 #
4 # Given a bar graph with two colors of bars, find the mean of two groups of data.
5 #
6 # Last edited by Carl Yao on 12/20/13
7 #
8 # ENDDESCRIPTION
9
10 ## DBCCSS('6.SP')
11 ## DBsubject(Statistics)
12 ## DBchapter(Exploratory data analysis/descriptive statistics)
13 ## DBsection(Summary statistics)
14 ## Institution(PCC)
15 ## Author(Carl Yao)
16 ## Level(2)
17 ## MO(1)
18 ## KEYWORDS('mean','application','bar graph')
19
20 ##############################################
21
22 DOCUMENT();
23
24 loadMacros(
25 "PGstandard.pl",
26 "PGgraphmacros.pl",
27 "MathObjects.pl",
28 "PGML.pl",
29 "contextPercent.pl",
30 "parserPopUp.pl",
31 "PCCmacros.pl",
32 "PGcourse.pl"
33 );
34
35 ##############################################
36
37 sub drawSquare {
38 my ($x,$y,$color) = @_;
39 $xside = ($xmax-$xmin)/40;
40 $yside = ($ymax-$ymin)/40;
41 $picture->moveTo($x,$y);
42 $picture->lineTo($x, $y-$yside, $color, 1);
43 $picture->lineTo($x+$xside, $y-$yside, $color, 1);
44 $picture->lineTo($x+$xside, $y, $color, 1);
45 $picture->lineTo($x, $y, $color, 1);
46 $picture->fillRegion([ $x+$xside/2, $y-$yside/2, $color ]);
47 }
48
49 sub sortSB {
50 my $ref_array = shift;
51 my $num = @$ref_array;
52 for my $i (0..$num-2) {
53 for my $j ($i+1..$num-1) {
54 if (${$ref_array}[$i]>${$ref_array}[$j]) {
55 (${$ref_array}[$i],${$ref_array}[$j]) = (${$ref_array}[$j],${$ref_array}[$i]);
56 }
57 }
58 }
59 }
60
61 ##############################################
62
63 Context("LimitedNumeric");
64
65 $numBars = 4;
66 $maxLimit = 30;
67
68 @terms = ("Fall","Winter","Spring","Summer");
69 @numMale = ();
70 @numFemale = ();
71
72 do {
73
74 $totalMale = 0;
75 $totalFemale = 0;
76
77 for my $i (0..$numBars-1) {
78 $numMale[$i] = int($maxLimit/2)+random(-1,1,2)*random(1,int($maxLimit/3),1);
79 $numFemale[$i] = $maxLimit - $numMale[$i];
80
81 $totalMale = $totalMale+$numMale[$i];
82 $totalFemale = $totalFemale+$numFemale[$i];
83 }
84
85 $meanMale = $totalMale/$numBars;
86 $meanFemale = $totalFemale/$numBars;
87
88 @numMaleSorted = @numMale;
89 sortSB(~~@numMaleSorted);
90 @numFemaleSorted = @numFemale;
91 sortSB(~~@numFemaleSorted);
92
93 $orderedMale = "";
94 $orderedFemale = "";
95 for my $i (0..$numBars-1) {
96 $orderedMale = $orderedMale."`$numMaleSorted[$i]`, ";
97 $orderedFemale = $orderedFemale."`$numFemaleSorted[$i]`, ";
98 }
99 chop($orderedMale);chop($orderedMale);
100 chop($orderedFemale);chop($orderedFemale);
101
102 $medianMale =
103 ($numMaleSorted[int($numBars/2)-1]+$numMaleSorted[int($numBars/2)])/2;
104 $medianFemale =
105 ($numFemaleSorted[int($numBars/2)-1]+$numFemaleSorted[int($numBars/2)])/2;
106
107 } until ( (($meanMale>$meanFemale) && ($medianMale<$medianFemale)) || (($meanMale<$meanFemale) && ($medianMale>$medianFemale)) );
108
109 $popup = PopUp(["?", "mean", "median"], "mean");
110
111 $yCover = $maxLimit;
112 $ystep = $yCover/6;
113 $xstep = 1;
114
115 $xmin = -$xstep; #The viewing window
116 $xmax = $numBars+2*$xstep;
117 $ymin = -$ystep;
118 $ymax = $yCover+$ystep;
119
120 $picture = init_graph($xmin,$ymin,$xmax,$ymax,
121 pixels=>[400,400]);
122 $picture->lb('reset');
123
124 $picture->moveTo(0,0);
125 $picture->lineTo($xmax-$xstep/2, 0, 'black',3);
126 $picture->moveTo(0,0);
127 $picture->arrowTo(0, $ymax-$ystep/2, 'black',3);
128
129 for my $i (0..$yCover/$ystep) {
130 $picture->stamps( closed_circle(0,$i*$ystep,'blue') );
131 $mark = $i*$ystep;
132 $picture->lb( new Label(-$xstep/2,$i*$ystep,"$mark",'black','center','middle'));
133 }
134
135 $picture->lb( new Label($xmax-$xstep/3,-$ystep/4,"terms",'black','right','middle'));
136 $picture->lb( new Label($xstep/4,$ymax-$ystep/3,"number of students",'black','left','middle'));
137
138 drawSquare($numBars-1,$ymax-$ystep/3,'red');
139 $picture->lb( new Label($numBars-1+$xstep/3,$ymax-$ystep/3,"male students",'red','left','top'));
140 drawSquare($numBars-1,$ymax-$ystep*2/3,'green');
141 $picture->lb( new Label($numBars-1+$xstep/3,$ymax-$ystep*2/3,"female students",'green','left','top'));
142
143 $alt = "This graph has two sets of bar graphs comparing male and female students in a certain class. ";
144 for my $i (0..$numBars-1) {
145 $picture->lb( new Label(($i+1)*$xstep,-$ystep/4,
146 $terms[$i],'black','center','middle'));
147
148 $picture->moveTo(($i+1-0.4)*$xstep,0);
149 $picture->lineTo(($i+1-0.4)*$xstep,$numMale[$i],'red',1);
150 $picture->lineTo(($i+1)*$xstep,$numMale[$i],'red',1);
151 $picture->lineTo(($i+1)*$xstep,0,'red',1);
152 $picture->fillRegion([ ($i+1-0.2)*$xstep,$numMale[$i]/2,'red' ]);
153 $picture->lb( new Label(($i+1-0.2)*$xstep,$numMale[$i]+$ystep/4,
154 "$numMale[$i]",'red','center','middle'));
155
156 $picture->moveTo(($i+1+0.4)*$xstep,0);
157 $picture->lineTo(($i+1+0.4)*$xstep,$numFemale[$i],'green',1);
158 $picture->lineTo(($i+1)*$xstep,$numFemale[$i],'green',1);
159 $picture->lineTo(($i+1)*$xstep,0,'green',1);
160 $picture->fillRegion([ ($i+1+0.2)*$xstep,$numFemale[$i]/2,'green' ]);
161 $picture->lb( new Label(($i+1+0.2)*$xstep,$numFemale[$i]+$ystep/4,
162 "$numFemale[$i]",'green','center','middle'));
163
164 $alt = $alt."In $terms[$i] Term, this class had $numMale[$i] male students and $numFemale[$i] female students. ";
165 }
166 chop($alt);
167
168 ##############################################
169
170 TEXT(beginproblem());
171 $refreshCachedImages = 1;
172
173 BEGIN_TEXT
174
175 This bar graph compares male and female student enrollment in a certain class at a community college in a certain school year. $PAR
176
177 $BCENTER
178 \{ image(insertGraph( $picture ), tex_size=>400, height=>400, width=>400, extra_html_tags => 'alt = "$alt" title = "$alt"') \}
179 $ECENTER
180 $PAR
181
182 END_TEXT
183 BEGIN_PGML
184
185 Answer the following questions.
186
187 *Question 1:* In these [`4`] terms, the mean number of male students in this class was [__________]{$meanMale}.
188
189 *Question 2:* In these [`4`] terms, the mean number of female students in this class was [__________]{$meanFemale}.
190
191 *Question 3:* In these [`4`] terms, the median of male students in this class was [__________]{$medianMale}.
192
193 *Question 4:* In these [`4`] terms, the median of female students in this class was [__________]{$medianFemale}.
194
195 *Question 5:* If you want to know, in all [`4`] terms, there are more male or female students, should you compare the mean or median?
196
197 [@$popup->menu()@]*
198
199 END_PGML
200
201 ##############################################
202
203 ANS( $popup->cmp() );
204
205 $midM1 = $numMaleSorted[$numBars/2-1];
206 $midM2 = $numMaleSorted[$numBars/2];
207 $outputM = "There are two numbers in the middle: `$midM1` and `$midM2`. The median is the mean of these two numbers: `\frac{$midM1+$midM2}{2}=$medianMale`.";
208
209 $midF1 = $numFemaleSorted[$numBars/2-1];
210 $midF2 = $numFemaleSorted[$numBars/2];
211 $outputF = "There are two numbers in the middle: `$midF1` and `$midF2`. The median is the mean of these two numbers: `\frac{$midF1+$midF2}{2}=$medianFemale`.";
212
213 if ($meanMale>$meanFemale) {
214 $output1 = "The mean of male students is bigger than that of female students, so more male students attended this class in all four terms. Notice that the median of female students is actually bigger than that of male students.";
215 } else {
216 $output1 = "The mean of female students is bigger than that of male students, so more female students attended this class in all four terms. Notice that the median of male students is actually bigger than that of female students.";
217 }
218
219 ##############################################
220
221 BEGIN_PGML_SOLUTION
222
223 ####Question 1
224
225 To find the mean number of male students in this class, we first add up the number of male students in all [`4`] terms:
226
227 [`` [@$numMale[0]@] + [@$numMale[1]@] + [@$numMale[2]@] + [@$numMale[3]@] = [$totalMale] ``]
228
229 Now we can find the mean by dividing the sum by the number of terms ([`4`]):
230
231 [`` \text{mean} = \frac{[$totalMale]}{4} = [$meanMale] ``]
232
233 *Solution:* In these [`4`] terms, the mean number of male students in this class was [`[$meanMale]`].
234
235 ----
236
237 ####Question 2
238
239 To find the mean number of female students in this class, we first add up the number of female students in all [`4`] terms:
240
241 [`` [@$numFemale[0]@] + [@$numFemale[1]@] + [@$numFemale[2]@] + [@$numFemale[3]@] = [$totalFemale] ``]
242
243 Now we can find the mean by dividing the sum by the number of terms ([`4`]):
244
245 [`` \text{mean} = \frac{[$totalFemale]}{4} = [$meanFemale] ``]
246
247 *Solution:* In these [`4`] terms, the mean number of female students in this class was [`[$meanFemale]`].
248
249 ----
250
251 ####Question 3
252
253 To find the median number of male students, we first need to order the number of male students in all [`4`] terms:
254
255 [$orderedMale]
256
257 [$outputM]
258
259 *Solution:* In these [`4`] terms, the median of male students in this class was [`[$medianMale]`].
260
261 ----
262
263 ####Question 4
264
265 To find the median number of female students, we first need to order the number of female students in all [`4`] terms:
266
267 [$orderedFemale]
268
269 [$outputF]
270
271 *Solution:* In these [`4`] terms, the median of female students in this class was [`[$medianFemale]`].
272
273 ----
274
275 ####Question 5
276
277 To compare the total number of male and female students in all [`4`] terms, we should compare the mean. The median is not accurate because some numbers were not considered; as a comparison, each number is used when the mean is calculated.
278
279 [$output1]
280
281 Don't think that the median is not useful. When there are outliers (very big or small numbers compared to most numbers in the group), the median is better than mean. That's why in newspapers, you will more than likely see "the median house price" than "the mean house price," etc.
282
283 END_PGML_SOLUTION
284
285 ENDDOCUMENT();