40 lines
756 B
Matlab
40 lines
756 B
Matlab
n = 10000;
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%% (a) simulate n times rolling a die:
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x = rollthedie( n );
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%% (b) probability P(3):
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P3 = sum(x == 3)/length(x);
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fprintf( 'P(3)=%.3f, expected is %.3f\n', P3, 1/6 );
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for i =1:6
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P = sum(x == i)/length(x);
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fprintf( 'P(%d)=%.3f, expected is %.3f\n', i, P, 1/6 );
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end
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%% (c) P(i)
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P = zeros(1, 6);
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for i =1:6
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P(i) = sum(x == i)/length(x);
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end
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subplot( 1, 2, 1 )
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plot( [0 7], [1/6 1/6], 'r', 'linewidth', 6 )
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hold on
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bar( P );
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hold off
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xlim( [ 0 7 ] );
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xlabel('Eyes');
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ylabel('Probability');
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%% (d) histogram of x
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subplot( 1, 2, 2 );
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diehist( x );
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%% (e) loaded die
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% eye 1 to 5 have P=1/8, eye 6 has P = 3/8 !
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x = randi( 8, 1, n ); % random numbers from 1 to 8
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x(x>6) = 6; % set numbers 7 and 8 to 6
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diehist( x );
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