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--- matlab:asciunqoc [2016/05/01 23:09] – created mithat
+++ matlab:asciunqoc [2021/12/07 20:32] (current) – mithat
@@ Line 1: / Line 1: @@
-====== MATLAB exercise solutions ======
+====== MATLAB exercise solutions (Century College, CSCI 1081, Fall 2021) ======
-Century College CSCI 1081
-Spring 2016
 <file matlab ex1.m>
@@ Line 11: / Line 9: @@
 <file matlab ex2.m>
-% not provided, but it's solvable!
+% not provided.
 </file>
-<file matlab ex.m>
+<file matlab ex3a.m>
+a = [2 3 1 5; 1 0 3 1; 0 2 -3 2; 0 2 3 1];
+% either works for multiplying a matrix with a scalar:
+disp(a * 7);
+disp(a .* 7);
+</file>
+<file matlab ex3b.m>
+a = [2 3 1 5; 1 0 3 1; 0 2 -3 2; 0 2 3 1];
+b = inv(a);
+disp(a * b); % result is (approx.) identity matrix
 </file>
-<file matlab ex.m>
+<file matlab ex3c.m>
+a = [2 3 1 5; 1 0 3 1; 0 2 -3 2; 0 2 3 1];
+b = [1 2 3; 10 20 30; 0.1 0.2 0.3];
+matrixinfo(a);
+matrixinfo(b); % square matrix of Inf values
 </file>
-<file matlab ex.m>
+<file matlab matrixinfo.m>
+function matrixinfo(m)
+% matrix_info(m)
+% Tell the user whether mtx is a square matrix. If it is a square matrix,
+% display the matrix's transpose and inverse.
+msize = size(m);
+if ndims(m) == 2 && msize(1) == msize(2),
+    disp('It''s a square matrix.');
+    disp('The transpose is:');
+    disp(m');
+    disp('The inverse is:');
+    disp(inv(m));
+else
+    disp('The matrix isn''t square.');
+end % if
+end % function
 </file>
-<file matlab ex.m>
+<file matlab Ch7PC5.m>
+% Input data for three monkeys
+NUM_MONKEYS = 3;
+NUM_DAYS = 5;
-</file>
+% initialize data to -1)
+data = ones(NUM_MONKEYS, NUM_MONKEYS) * -1;
+% Get monkey data
+for monkey = 1:NUM_MONKEYS,
+    disp('----------');
+    % enter row data as days of week
+    for day = 1:NUM_DAYS,
+        is_valid = false;
+        while ~is_valid,
+            prompt = ['Monkey ' num2str(monkey) ', day ' num2str(day) ': '];
+            data(monkey, day) = input(prompt);
+            is_valid = data(monkey, day) >= 0;
+            if ~is_valid,
+                disp('Try again.');
+            end; % if
+        end % while
+    end % inner for
+end % outer for
+% for each column, compute the average:
+avgeaten = zeros(1, NUM_DAYS);
+for day = 1:NUM_DAYS,
+    avgeaten(day) = mean(data(:, day));
+end % for
-<file matlab ex.m>
+% Display report
+disp('=====================================');
+disp('The average amount eaten on each day:');
+disp(avgeaten);
+disp(['The least amount eaten this week: ' num2str(min(min(data))) ]);
+disp(['The greatest amount eaten this week: ' num2str(max(max(data))) ]);
+disp('=====================================');
 </file>