[4, 2, 3](1) [4, 2, 3](1) | {Error: Unbalanced or unexpected parenthesis or bracket. } [ ] ans = [] sin( 4 ) ans = -0.7568 (3 + 5)/4 ans = 2 a = [4 2 3]; a(1) ans = 4 a(0) {Subscript indices must either be real positive integers or logicals. } a(4) {Index exceeds matrix dimensions. } a(-1) {Index exceeds matrix dimensions. } rand( 2, 4 ) ans = 0.8147 0.1270 0.6324 0.2785 0.9058 0.9134 0.0975 0.5469 rand( 2, 4, 3 ) ans(:,:,1) = 0.9575 0.1576 0.9572 0.8003 0.9649 0.9706 0.4854 0.1419 ans(:,:,2) = 0.4218 0.7922 0.6557 0.8491 0.9157 0.9595 0.0357 0.9340 ans(:,:,3) = 0.6787 0.7431 0.6555 0.7060 0.7577 0.3922 0.1712 0.0318 rand( 2, 4, 3, 1 ) ans(:,:,1) = 0.2769 0.0971 0.6948 0.9502 0.0462 0.8235 0.3171 0.0344 ans(:,:,2) = 0.4387 0.7655 0.1869 0.4456 0.3816 0.7952 0.4898 0.6463 ans(:,:,3) = 0.7094 0.2760 0.6551 0.1190 0.7547 0.6797 0.1626 0.4984 rand( 2, 4, 3, 2 ) ans(:,:,1,1) = 0.9597 0.5853 0.7513 0.5060 0.3404 0.2238 0.2551 0.6991 ans(:,:,2,1) = 0.8909 0.5472 0.1493 0.8407 0.9593 0.1386 0.2575 0.2543 ans(:,:,3,1) = 0.8143 0.9293 0.1966 0.6160 0.2435 0.3500 0.2511 0.4733 ans(:,:,1,2) = 0.3517 0.5853 0.9172 0.7572 0.8308 0.5497 0.2858 0.7537 ans(:,:,2,2) = 0.3804 0.0759 0.5308 0.9340 0.5678 0.0540 0.7792 0.1299 ans(:,:,3,2) = 0.5688 0.0119 0.1622 0.3112 0.4694 0.3371 0.7943 0.5285 rand( 3, 4 ) ans = 0.1656 0.6541 0.4505 0.9133 0.6020 0.6892 0.0838 0.1524 0.2630 0.7482 0.2290 0.8258 rand( 3, 4 ) * rand( 4, 1 ) ans = 1.2871 0.7554 1.5066 A = rand(3, 4) A = 0.1818 0.1361 0.5499 0.6221 0.2638 0.8693 0.1450 0.3510 0.1455 0.5797 0.8530 0.5132 b = rand(4,1) b = 0.4018 0.0760 0.2399 0.1233 b = rand(1,4) b = 0.1839 0.2400 0.4173 0.0497 A*b {Error using * Inner matrix dimensions must agree. } A*b' ans = 0.3264 0.3350 0.5473 b*A {Error using * Inner matrix dimensions must agree. } b b = 0.1839 0.2400 0.4173 0.0497 A = rand(4, 4) A = 0.9027 0.3377 0.7803 0.0965 0.9448 0.9001 0.3897 0.1320 0.4909 0.3692 0.2417 0.9421 0.4893 0.1112 0.4039 0.9561 b*A ans = 0.6218 0.4377 0.3579 0.4900 [ 1 2 3, 1, 3, 4 ] ans = 1 2 3 1 3 4 whos( [ 1 2 3, 1, 3, 4 ] ) {Error using whos Argument must contain a string. } a = [ 1 2 3, 1, 3, 4 ] a = 1 2 3 1 3 4 whos('a') Name Size Bytes Class Attributes a 1x6 48 double a = [ 1 2 3; 1, 3, 4 ] a = 1 2 3 1 3 4 whos('a') Name Size Bytes Class Attributes a 2x3 48 double a = [ 1 2 3; 1, 4 ] {Error using vertcat Dimensions of matrices being concatenated are not consistent. } A = [1 2 3]; B = [-1 1; 1 -1]; C = [ B , C = [ B, B; A pi ] C = -1.0000 1.0000 -1.0000 1.0000 1.0000 -1.0000 1.0000 -1.0000 1.0000 2.0000 3.0000 3.1416 C = [ B B; A pi ] C = -1.0000 1.0000 -1.0000 1.0000 1.0000 -1.0000 1.0000 -1.0000 1.0000 2.0000 3.0000 3.1416 C = [ B B B; A A ] C = -1 1 -1 1 -1 1 1 -1 1 -1 1 -1 1 2 3 1 2 3 [[ B; B ], [ pi; rand(2,1); pi ]] ans = -1.0000 1.0000 3.1416 1.0000 -1.0000 0.5752 -1.0000 1.0000 0.0598 1.0000 -1.0000 3.1416 rand(3, 4) ans = 0.2348 0.0154 0.6491 0.4509 0.3532 0.0430 0.7317 0.5470 0.8212 0.1690 0.6477 0.2963 rand(3) ans = 0.7447 0.1835 0.7802 0.1890 0.3685 0.0811 0.6868 0.6256 0.9294 rand(3,1) ans = 0.7757 0.4868 0.4359 rand(1,3) ans = 0.4468 0.3063 0.5085 rand(4) ans = 0.5108 0.3786 0.9390 0.5870 0.8176 0.8116 0.8759 0.2077 0.7948 0.5328 0.5502 0.3012 0.6443 0.3507 0.6225 0.4709 rand(10,1) ans = 0.2305 0.8443 0.1948 0.2259 0.1707 0.2277 0.4357 0.3111 0.9234 0.4302 randn(10,1) ans = -1.0642 1.6035 1.2347 -0.2296 -1.5062 -0.4446 -0.1559 0.2761 -0.2612 0.4434 A = rand(3,4) A = 0.7112 0.2967 0.5079 0.8010 0.2217 0.3188 0.0855 0.0292 0.1174 0.4242 0.2625 0.9289 size(A) ans = 3 4 [m,n] = size(A) m = 3 n = 4 m = size(A) m = 3 4 whos('m') Name Size Bytes Class Attributes m 1x2 16 double m(2) ans = 4 A = rand(5) A = 0.7303 0.9631 0.6241 0.0377 0.2619 0.4886 0.5468 0.6791 0.8852 0.3354 0.5785 0.5211 0.3955 0.9133 0.6797 0.2373 0.2316 0.3674 0.7962 0.1366 0.4588 0.4889 0.9880 0.0987 0.7212 lu(A) ans = 0.7303 0.9631 0.6241 0.0377 0.2619 0.7921 -0.2418 -0.0988 0.8834 0.4723 0.6283 0.4806 0.6434 -0.3495 0.3297 0.6690 0.4034 0.4686 0.6674 -0.1849 0.3249 0.3363 0.3076 0.8906 -0.0442 M = lu(A) M = 0.7303 0.9631 0.6241 0.0377 0.2619 0.7921 -0.2418 -0.0988 0.8834 0.4723 0.6283 0.4806 0.6434 -0.3495 0.3297 0.6690 0.4034 0.4686 0.6674 -0.1849 0.3249 0.3363 0.3076 0.8906 -0.0442 [L,U] = lu(A) L = 1.0000 0 0 0 0 0.6690 0.4034 0.4686 1.0000 0 0.7921 1.0000 0 0 0 0.3249 0.3363 0.3076 0.8906 1.0000 0.6283 0.4806 1.0000 0 0 U = 0.7303 0.9631 0.6241 0.0377 0.2619 0 -0.2418 -0.0988 0.8834 0.4723 0 0 0.6434 -0.3495 0.3297 0 0 0 0.6674 -0.1849 0 0 0 0 -0.0442 [L,U,p] = lu(A) L = 1.0000 0 0 0 0 0.7921 1.0000 0 0 0 0.6283 0.4806 1.0000 0 0 0.6690 0.4034 0.4686 1.0000 0 0.3249 0.3363 0.3076 0.8906 1.0000 U = 0.7303 0.9631 0.6241 0.0377 0.2619 0 -0.2418 -0.0988 0.8834 0.4723 0 0 0.6434 -0.3495 0.3297 0 0 0 0.6674 -0.1849 0 0 0 0 -0.0442 p = 1 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 1 0 A A = 0.7303 0.9631 0.6241 0.0377 0.2619 0.4886 0.5468 0.6791 0.8852 0.3354 0.5785 0.5211 0.3955 0.9133 0.6797 0.2373 0.2316 0.3674 0.7962 0.1366 0.4588 0.4889 0.9880 0.0987 0.7212 diag(A) ans = 0.7303 0.5468 0.3955 0.7962 0.7212 diag([1 2 3 4 5]) ans = 1 0 0 0 0 0 2 0 0 0 0 0 3 0 0 0 0 0 4 0 0 0 0 0 5 diag(diag(A)) ans = 0.7303 0 0 0 0 0 0.5468 0 0 0 0 0 0.3955 0 0 0 0 0 0.7962 0 0 0 0 0 0.7212 diag([1,2,3,4],2) ans = 0 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 3 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 diag([1,2,3,4],-2) ans = 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 3 0 0 0 0 0 0 4 0 0 1 0 0 0 0 0 1 0 0 0 0 0 | {Error: Unexpected MATLAB expression. } [ ] ans = [] rand ans = 0.1068 randn ans = 0.0662 diag {Error using diag Not enough input arguments. } zeros(4,5) ans = 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 zeros(4) ans = 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ones(4) ans = 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 twos(4) {Undefined function or variable 'twos'. } eye(4) ans = 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 A A = 0.7303 0.9631 0.6241 0.0377 0.2619 0.4886 0.5468 0.6791 0.8852 0.3354 0.5785 0.5211 0.3955 0.9133 0.6797 0.2373 0.2316 0.3674 0.7962 0.1366 0.4588 0.4889 0.9880 0.0987 0.7212 A * eye(5) ans = 0.7303 0.9631 0.6241 0.0377 0.2619 0.4886 0.5468 0.6791 0.8852 0.3354 0.5785 0.5211 0.3955 0.9133 0.6797 0.2373 0.2316 0.3674 0.7962 0.1366 0.4588 0.4889 0.9880 0.0987 0.7212 A*eye(5) == diag(diag(A)) ans = 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 linspace(1,10,11) ans = Columns 1 through 8 1.0000 1.9000 2.8000 3.7000 4.6000 5.5000 6.4000 7.3000 Columns 9 through 11 8.2000 9.1000 10.0000 linspace(1,10,9) ans = Columns 1 through 8 1.0000 2.1250 3.2500 4.3750 5.5000 6.6250 7.7500 8.8750 Column 9 10.0000 linspace(1,10,10) ans = 1 2 3 4 5 6 7 8 9 10 linspace(1,10,11) ans = Columns 1 through 8 1.0000 1.9000 2.8000 3.7000 4.6000 5.5000 6.4000 7.3000 Columns 9 through 11 8.2000 9.1000 10.0000 1:10 ans = 1 2 3 4 5 6 7 8 9 10 1:1.1:10 ans = Columns 1 through 8 1.0000 2.1000 3.2000 4.3000 5.4000 6.5000 7.6000 8.7000 Column 9 9.8000 1:2:8 ans = 1 3 5 7 8:-2:1 ans = 8 6 4 2 a = [1 2 3 4 5 6] a = 1 2 3 4 5 6 a(4) ans = 4 a(4:6) ans = 4 5 6 a([4 5 6]) ans = 4 5 6 a = [1.1 2.2 3.3 4.3 5.2 6.1] a = 1.1000 2.2000 3.3000 4.3000 5.2000 6.1000 a(4:6) ans = 4.3000 5.2000 6.1000 a([4 5 6]) ans = 4.3000 5.2000 6.1000 a([4, 5, 6]) ans = 4.3000 5.2000 6.1000 a([4; 5; 6]) ans = 4.3000 5.2000 6.1000 a(4:end) ans = 4.3000 5.2000 6.1000 4:end 4:end | {Error: Illegal use of reserved keyword "end". } a(end) ans = 6.1000 a(end-1) ans = 5.2000 a(1:end) ans = 1.1000 2.2000 3.3000 4.3000 5.2000 6.1000 a(:) ans = 1.1000 2.2000 3.3000 4.3000 5.2000 6.1000 a(2:end) ans = 2.2000 3.3000 4.3000 5.2000 6.1000 a a = 1.1000 2.2000 3.3000 4.3000 5.2000 6.1000 a(end:-2:3) ans = 6.1000 4.3000 1:24 ans = Columns 1 through 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Columns 15 through 24 15 16 17 18 19 20 21 22 23 24 reshape(1:24, 6, 4) ans = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 reshape(1:24, 2, 4, 3) ans(:,:,1) = 1 3 5 7 2 4 6 8 ans(:,:,2) = 9 11 13 15 10 12 14 16 ans(:,:,3) = 17 19 21 23 18 20 22 24 reshape(1:24, 6, 4) ans = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 A = reshape(1:24, 6, 4) A = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 A( 3, 0 ) {Subscript indices must either be real positive integers or logicals. } A( 3, 1 ) ans = 3 A( 1, 3 ) ans = 13 A( 10 ) ans = 10 A( 6 ) ans = 6 A A = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 A(:) ans = 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 A A = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 A(3,end) ans = 21 A(3:end) ans = Columns 1 through 14 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Columns 15 through 22 17 18 19 20 21 22 23 24 A(3,:) ans = 3 9 15 21 A(:,3) ans = 13 14 15 16 17 18 A A = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 2:4 ans = 2 3 4 A(2:4,3:4) ans = 14 20 15 21 16 22 A A = 1 7 13 19 2 8 14 20 3 9 15 21 4 10 16 22 5 11 17 23 6 12 18 24 A(5:7,2:3) {Index exceeds matrix dimensions. } A(5:6,2:3) ans = 11 17 12 18 A(6:-1:5,2:3) ans = 12 18 11 17 A(6:5,2:3) ans = Empty matrix: 0-by-2 A(6:5,2:3) * rand(2,5) ans = Empty matrix: 0-by-5 rand(4,0) * A(6:5,2:3) ans = 0 0 0 0 0 0 0 0 b = [ 7 6 5 4 3 ]; a = b(end:-1:3); b = [ 7 6 5 4 3 ] b = 7 6 5 4 3 b = [ 7 6 5 4 3 ]' b = 7 6 5 4 3 b = [ 7 6 5 4 3 ] b = 7 6 5 4 3 a = b(end:-1:3) a = 3 4 5 b b = 7 6 5 4 3 a a = 3 4 5 b b = 7 6 5 4 3 b([5 4 4 3]) ans = 3 4 4 5 a = b([[1:3 2 2 2 3], [1 2 3]]) a = 7 6 5 6 6 6 5 7 6 5 clear('a') a {Undefined function or variable 'a'. } a(3) = b(4) a = 0 0 4 whos('a') Name Size Bytes Class Attributes a 1x3 24 double a(6) = b(4) a = 0 0 4 0 0 4 A = rand(3) A = 0.4799 0.6177 0.5767 0.9047 0.8594 0.1829 0.6099 0.8055 0.2399 A(5,4) = pi A = 0.4799 0.6177 0.5767 0 0.9047 0.8594 0.1829 0 0.6099 0.8055 0.2399 0 0 0 0 0 0 0 0 3.1416 a a = 0 0 4 0 0 4 b b = 7 6 5 4 3 a( end:-2:1 ) = rand( 1,3 ) a = 0 0.4899 4.0000 0.0287 0 0.8865 a( end:-3:1 ) = rand( 1,2 ) a = 0 0.4899 0.9787 0.0287 0 0.1679 a( end:-3:1 ) = rand( 1,3 ) {In an assignment A(I) = B, the number of elements in B and I must be the same. } a( [3 5 2] ) = rand( 1,3 ) a = 0 0.0424 0.0596 0.0287 0.6820 0.1679 diary