>> yv = magic(4) yv = 16 2 3 13 5 11 10 8 9 7 6 12 4 14 15 1 >> y = [3;4;2;1] y = 3 4 2 1
yv=[1:num_labels] == y數組
>> yv = [1:4] == y yv = 4×4 logical 數組 0 0 1 0 0 0 0 1 0 1 0 0 1 0 0 0
yv = zeros(m, num_labels);
for i = 1:m
yv(i, y(i)) = 1;
end測試
>> yv = zeros(4,4) yv = 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 >> for i = 1:4 yv(i, y(i)) = 1; end >> yv yv = 0 0 1 0 0 0 0 1 0 1 0 0 1 0 0 0
all_combos = eye(num_labels);
y_matrix = all_combos(y,:)code
>> all_combos = eye(4); >> y_matrix = all_combos(y,:) y_matrix = 0 0 1 0 0 0 0 1 0 1 0 0 1 0 0 0