10/18/18-12:38:31 PM CDT

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1 Online Homework System Assignment Worksheet 10/18/18-12:38:31 PM CDT Name: Class: Class #: Section #: Instructor: Ryan Patrick Assignment Instructions: Assignment: Midterm Exam Select all answers that apply. The note PDFs you submitted are available at ( Question 1: (6 points) Which values for ourvector will allow the statement ourvector( 1 : 2 : 7 ) to produce the result ? (a) [ ] (b) [ ] (c) [ ] (d) [ ] (e) [ ] Question 2: (6 points) Which values for ourmatrix will allow the statement ourmatrix( 1 : 2, 1 ) to produce the result [ 5 8 ]'? (a) [ 5 9 3; 8 7 4; 4 1 3; ] (b) [ ; ] (c) [ 5 8; 5 8; 5 8 ] (d) [ 5 8 ]' (e) [ 5 9; 8 7; 2 4; 6 7 ]

2 Question 3: (6 points) Which value(s) for ourvalues would produce [ ] for the statement ourvalues( ourvalues >= 5 )? (a) [ ] (b) [ ] (c) [ ] (d) [ ] (e) [ ] Question 4: (6 points) Which value(s) for ourvalues would produce 1 for the statement all( ourvalues > 1 )? (a) [ ] (b) [ ] (c) 2 : 9 (d) [ ] (e) 6 : 6 Question 5: (6 points) Which value(s) for ourvalues would produce for the statement abs(ourvalues) >= 4? (a) [ ] (b) [ ] (c) [ ] (d) [ ] (e) [ ]

3 Question 6: (6 points) Given this code written with while loops ii = -10; while ii <= 10 jj = 0; while jj <= 5 fprintf('%d %d\n', ii, jj) jj = jj + 1; ii = ii + 2; Which of the following loops using for yield the same results? for ii = -10 : 2 : 10 for jj = 0 : 5 fprintf( '%d %d\n', ii, jj ) (a) for ii = -5 : 5 for jj = 0 : 5 fprintf( '%d %d\n', 2 * ii, jj ) (b) ii = -10; for ii = -10 : 2 : 10 jj = 0; for jj = 0 : 5 (c) fprintf( '%d %d\n', ii, jj )

4 ii = -10; for ii = -10 : 2 : 10 jj = 0; for jj = 0 : 5 fprintf( '%d %d\n', ii, jj ) (d) jj = jj + 1; ii = ii + 2; for ii = -10 : 2 : 10 for jj = 0 : 5 fprintf( '%d %d\n', ii, jj ) jj = jj + 1; (e) ii = ii + 2;

5 Question 7: (7 points) Given this interaction, what is the value of positions? >> disp( matrix ); >> disp( size( positions ) ); 1 4 >> disp( matrix( positions ) ); (a) [ ] (b) [ ] (c) [ ] (d) [ 4 1; 1 1; 2 4; 2 4 ] (e) [ ]

6 Question 8: (7 points) Given this code (in the file input1188.m) % input1188.m ourmatrix = [ 10 : 10 : 30; 40 : 10: 60; 70 : 10 : 90 ]; disp( ourmatrix( input( 'Position: ') ) ); and this interaction >> input88 Position:??? 60 What could the user enter (where the??? is shown) to cause this result to display? (a) [ 2 3 ] (b) [ 3 2 ] (c) ( 2 3 ) (d) 8 (e) 3 2 Question 9: (6 points) Given this interaction, what would be displayed if disp( inds ) was called? >> values = 100 : -10 : -100; >> disp( values( inds ) ) (a) (b) [ ] (c) (d) [ ] (e) [ ] Question 10: (6 points) Which of the following code fragments does not yield the same results? If all do yield the same results, mark none of them.

7 if x < 0 y = 1; elseif x == 0 y = 2; (a) else y = 3; if x < 0 y = 1; if x == 0 y = 2; (b) if x > 0 y = 3; y = 1; if x == 0 y = 2; else (c) y = 3; y = 1; if x == 0 y = y + 1; elseif x > 0 (d) y = y + 2;

8 if x < 0 y = 1; else if x == 0 y = 2; (e) else y = 3; Question 11: (7 points) Consider the following code segment. count = 0; for a = 1 : n for b = 1 : n count = count + 1; for c = 1 : n count = count + 1; for d = 1 : n for e = 1 : n count = count + 1; disp(count) What expression is calculated and displayed at the of the code? (a) n ^ 4 + n ^ 3 (b) 2 * n ^ 2 * n ^ 3 (c) n ^ 2 + n ^ 3 (d) 2 * n ^ 2 + n ^ 3 (e) 3 * n

9 Question 12: (6 points) Which values for ourvector will allow the statement ourvector( 4 : -3 : -1 ) to produce the result 5 1? (a) [ ] (b) Nothing (an error would occur) (c) [ ] (d) [ ] (e) [ ] Question 13: (6 points) Which values for ourmatrix will allow the statement ourmatrix( :, 2 )' to produce the result 3 6 9? (a) [ 6 3 9; 6 4 8; ; ] (b) [ 3 3 9; 9 6 6; ] (c) [ ] (d) [ 4 3 7; 6 6 8; 2 9 3; ] (e) [ 4 3 6; 6 6 8; ]

10 Question 14: (6 points) Consider the following anonymous functions with sample executions (results not shown). Mark the true statements. (Recall that in a vector refers to the last element.) >> fun1 =@ (v, list) [ list < v, list > v ]; >> fun1( 12, [ ] ); >> fun2 =@ (v, list) [ list( v+1 : ) list( 1 : v ) ] >> fun2( 2, [ ]); (a) fun2 moves the first v elements of list to the right. (b) fun1 removes all instances of v from list (c) fun1 partitions list so that elements smaller than v go to the left and elements larger go to the right. (d) fun1 leaves list sorted if it was originally sorted (in increasing order) (e) fun2 moves the first v+1 elements of list to the right. Question 15: (6 points) Assume x = [ ; ; ]; Indicate which of the following expressions yields [ 42 36; ] (a) reshape( x( fix( 4 : 1.5 : 8:5 ), 2, 2 ) (b) x( [1 2 ], [ 2 3 ] ) (c) reshape( x( x > 30 ), 2, 2 ) (d) x( [ 4 7; 5 8 ] ) (e) x( 1 2, 2 3 )

11 Question 16: (7 points) Consider the following interaction >> mystery01( 'D', 'T' ) ans = 16 >> mystery01( 'O', 'F' ) ans = -9 >> mystery01( 'V', 'T' ) ans = -2 Which statements could be used by another program/script to calculate the distance between 'S' and 'C'? (a) mystery01( 'S', 'C' ) (b) mystery01( 'C', 'L' ) + mystery01( 'L', 'S' ) (c) mystery01( 'S', mystery01( 'N', 'C' ) ) (d) abs( mystery01( 'S', 'N' ) + mystery01( 'L', 'C' ) ) (e) abs( mystery01( 'S', 'N' ) ) + abs( mystery01( 'N', 'C' ) )