close all
clear all

logintimeout(5);
DSN = 'CS3331-SCORE';

% ====== Get homework/quiz score
Conn = database(DSN, '', '');
%ping(Conn)
cursorA = exec(Conn, 'select * from combined');
cursorA = fetch(cursorA);
A = cursorA.data;
close(cursorA);
close(Conn);

id  = [A{:,1}]';
name  = A(:,2);	% This big-5 strings are trashed already!
hw1 = [A{:,4}]';
hw2 = [A{:,5}]';
hw3 = [A{:,6}]';
hw4 = [A{:,7}]';
quiz1 = [A{:,8}]';
quiz2 = [A{:,9}]';
quiz3 = [A{:,10}]';
quiz4 = [A{:,11}]';
quiz5 = [A{:,12}]';

student_n = length(id);
hw = [hw1 hw2 hw3 hw4];
quiz = [quiz1 quiz2 quiz3 quiz4 quiz5];

% ====== Find the average of each quiz, excluding 0 score
temp = quiz;
% ====== Replace 0's with NaN's
temp(find(temp==0)) = nan;
% ====== Display mean of quiz ===>  35.7611 38.0265 24.7321 35.5088 34.2700
% nanmean(temp)
% ====== The average of quiz 3 is too low ...
quiz(:,3) = quiz(:,3)+10;

% ====== Start the real computation
hw_sum = sum(hw')';
quiz_sum = sum(quiz')'-min(quiz')';	% The lowest score is not used

% ====== Normalize to [0, 1]
max_hw_sum = 100+80+100+80;
max_quiz_sum = 200;
%norm_hw_sum = hw_sum/max(hw_sum);
%norm_quiz_sum = quiz_sum/max(quiz_sum);
norm_hw_sum = hw_sum/max_hw_sum;
norm_quiz_sum = quiz_sum/max_quiz_sum;
norm_final = 0.3*norm_hw_sum + 0.7*norm_quiz_sum;
%norm_final = (norm_final-min(norm_final))/(max(norm_final)-min(norm_final));

% Distortion 
expo = 0.8;
norm_final = 1-(1-norm_final).^expo;

% Normalize to a proper range
%maximum = 95; minimum = 40;
%final_score = norm_final*(maximum-minimum) + minimum;
final_score = 100*norm_final;
score = round(final_score)+2;
ave_score = mean(score);
med_score = median(score);

% ====== scores between 50 and 60 become 60 
score(find(50<score & score<60)) = 60;
% ====== 69 become 70 
score(find(score==69)) = 70;
% ====== 79 become 80 
score(find(score==79)) = 80;

% ====== Send the final overall scores back to the database
Conn = database(DSN, '', '');
colnames = {'Overall'};
fprintf('Inserting the overall scores back to the database ... \n');
for i = 1:length(id),
	whereclause = ['where id = ', num2str(id(i))];
	update(Conn, 'combined', colnames, {score(i)}, whereclause);
end
close(Conn);

% ====== Write the final overall scores to a file for score listing
filename = 'score.txt';
fprintf('Writing the overall scores to file "%s" ... \n', filename);
fid=fopen(filename, 'w');
fprintf(fid, '%s\t', 'ID');
fprintf(fid, '%s\t', 'hw1');
fprintf(fid, '%s\t', 'hw2');
fprintf(fid, '%s\t', 'hw3');
fprintf(fid, '%s\t', 'hw4');
fprintf(fid, '%s\t', 'quiz1');
fprintf(fid, '%s\t', 'quiz2');
fprintf(fid, '%s\t', 'quiz3');
fprintf(fid, '%s\t', 'quiz4');
fprintf(fid, '%s\t', 'quiz5');
fprintf(fid, '%s\n', 'Overall');
for i = 1:student_n,
	fprintf(fid, '%s\t', num2str(id(i, :)));
	fprintf(fid, '%g\t', hw1(i));
	fprintf(fid, '%g\t', hw2(i));
	fprintf(fid, '%g\t', hw3(i));
	fprintf(fid, '%g\t', hw4(i));
	fprintf(fid, '%g\t', quiz1(i));
	fprintf(fid, '%g\t', quiz2(i));
	fprintf(fid, '%g\t', quiz3(i));
	fprintf(fid, '%g\t', quiz4(i));
	fprintf(fid, '%g\t', quiz5(i));
	fprintf(fid, '%g\n', score(i));
end
fprintf(fid, '\n');
fprintf(fid, 'Average =  %2.1f\n', ave_score);
fprintf(fid, 'Median  =  %2.1f\n', med_score);
fclose(fid);

% ====== Plotting
fprintf('Plotting the result and statistics ...\n');
% ====== Reordering according to final overall score
[a b] = sort(score);
sorted_score = score(flipud(b));
sorted_id = id(flipud(b), :);

% ====== Display scores
x = (1:student_n)';
colordef(gcf, 'black');
subplot(211);
plot(x, sorted_score, '-', x, sorted_score, 'o');
tmp = x(:, ones(1, 3))';
X = tmp(:);
tmp = [min(sorted_score)*ones(student_n,1) sorted_score nan*ones(student_n,1)]';
Y = tmp(:);
hold on; plot(X, Y, 'g:'); hold off;
axis([1 length(sorted_score) -inf inf]);
set(gca, 'xticklabels', []);
ylabel('Scores');

% ====== Add text of input variables
for k = 1:student_n,
	text(x(k), min(sorted_score), num2str(sorted_id(k,:)));
%	text(x(k), min(sorted_score), [num2str(sorted_id(k,:)), name{k}]);
end
h = findobj(gcf, 'type', 'text');
set(h, 'rot', 90, 'fontsize', 6, 'hori', 'right');
title(['CS3331 (Numerical Methods) scores statistics: average = ', ...
	num2str(ave_score), ', median = ', ...
	num2str(med_score)]);
grid on
hold on
plot([1 student_n], [med_score med_score], 'c');
plot((student_n+1)/2*[1 1], [min(sorted_score) max(sorted_score)], 'c');
hold off

subplot(212);
hist(sorted_score, 5:10:95);
title('Histogram');
xlabel('Scores');
ylabel('Student Numbers');