sum of series of matrix

7 次查看(过去 30 天)
I have a series of matrices like A1, A2,.........A99. I want to find sum of three matrices like(A1+A2+A3) then (A4+A5+A6)........(A97+A98+A99)
  2 个评论
Chunru
Chunru 2022-8-16
Can you put your matrices into a single 3D array like A(i,j,k)?
rakesh kumar
rakesh kumar 2022-8-16
yes, but my problem is that have to find the sum in groups as I have mentioned. Thanks in advance for your help.

请先登录,再进行评论。

采纳的回答

Chunru
Chunru 2022-8-16
A = randn(5, 5, 99);
B = zeros(5, 5, 33);
for i=1:33
B(:, :, i) = sum(A(:, :, (i-1)*3+(1:3)), 3);
end
whos
Name Size Bytes Class Attributes A 5x5x99 19800 double B 5x5x33 6600 double cmdout 1x33 66 char i 1x1 8 double
B
B =
B(:,:,1) = 1.0801 -0.9310 1.6476 3.9098 -0.1822 2.7773 1.0514 2.8541 -1.9000 0.6120 1.0582 -0.4614 0.8884 0.4824 0.5554 -0.5364 0.4871 0.6735 -0.6918 0.7854 -2.3907 1.8485 0.3522 -3.2762 -2.1711 B(:,:,2) = 1.7186 0.5920 3.6962 2.1688 0.1163 -0.7519 -1.6879 3.1578 -3.1428 1.4388 0.0607 2.9797 0.7485 0.6620 0.0260 1.8920 -3.0542 1.0073 1.4882 -0.6512 -4.2737 -0.4719 0.9764 0.6908 1.9635 B(:,:,3) = -1.1917 -0.1001 0.9368 -1.9018 0.7090 1.5334 1.7555 2.1941 -0.6463 -0.1665 -0.2419 0.3022 0.3150 -3.5558 1.1313 -1.6839 0.6759 0.0532 2.8834 4.0220 -0.1851 1.4545 2.3745 -1.1610 1.2608 B(:,:,4) = 0.6287 1.9192 -1.0544 -1.2425 -2.8365 1.4835 0.5123 4.1524 -1.1864 0.1390 0.7249 -0.1715 0.3567 -1.1869 2.5121 -1.0874 1.2256 -0.4822 1.7408 -0.8053 -0.7387 1.7543 1.1213 -4.0384 -0.8762 B(:,:,5) = 0.9368 0.3619 1.2844 -1.2814 -1.2918 -1.4238 0.3363 1.5450 0.0269 -1.8170 0.6068 0.5592 2.0891 -0.9862 -0.2391 -0.4027 -0.5556 -0.5730 1.7127 1.1396 1.8389 -1.2629 3.5192 0.3103 2.6123 B(:,:,6) = -3.2745 1.2307 -1.4399 3.2468 -2.8418 -0.9268 -2.3572 1.5603 1.1992 0.8358 0.3286 -0.3112 0.3418 0.1299 0.3077 0.1179 1.6223 -1.6759 3.0819 0.5428 3.4974 0.7914 1.4008 -0.8006 2.3222 B(:,:,7) = 3.8006 1.8363 2.5171 -0.0303 0.9158 2.4714 0.0860 -1.7693 -0.4328 0.2005 2.2799 -0.9735 -1.7687 0.4138 2.9406 -1.0887 1.7944 1.0271 0.7926 1.2619 -1.3412 -1.9069 2.7119 -3.4371 1.1389 B(:,:,8) = -1.7138 2.3615 2.5694 -0.4497 -4.5408 -1.5113 0.7602 2.1105 -0.3170 -2.6361 -3.1610 -1.4643 0.6216 2.8660 0.0573 -1.6175 4.0008 -0.3381 -0.1984 -0.7947 -1.7819 0.4095 -1.4420 1.5145 -0.3211 B(:,:,9) = 2.3838 2.0878 -0.5382 3.7507 2.0960 1.9347 2.0669 -0.8329 0.3824 0.8640 2.4861 -2.6501 1.7428 -1.7890 -1.6104 -0.7959 0.3277 4.8707 -0.2208 1.2169 -1.9939 -0.6632 -0.0665 -1.7913 1.4307 B(:,:,10) = 1.7708 0.8174 -2.7081 0.5897 -0.6022 -0.1805 0.3482 -1.1240 0.8698 -0.2955 -0.9489 1.3042 -4.6263 1.7611 0.8033 -1.0393 -1.3906 -2.6551 -0.4666 0.3346 2.1117 0.6587 0.1391 -2.2200 1.9483 B(:,:,11) = -1.6108 3.9748 2.3733 -1.2794 -1.1346 1.5313 2.6586 1.2973 1.1206 -0.6783 0.2285 1.3468 -0.3297 -1.4879 0.9589 -3.2108 3.4015 1.2998 -3.2940 0.4316 -1.2495 -3.5360 2.1075 -0.1034 -1.3260 B(:,:,12) = 0.0661 -1.7048 1.9452 3.1399 -3.0431 -0.6224 -1.3920 2.7349 1.5759 1.9048 -2.6062 0.1277 3.5493 0.0089 -6.0951 0.2745 -0.9913 -3.8000 -2.1058 0.0014 -0.6025 -0.3238 0.7430 1.2486 0.3905 B(:,:,13) = 0.5090 -1.8384 4.9040 -0.0834 0.9401 -2.5016 -1.0498 -0.9617 0.1988 -1.6728 3.1996 -2.7104 2.0117 1.0260 -0.3569 3.2603 3.1382 3.0901 0.0855 -0.6663 0.7472 1.9691 0.4188 0.2657 -0.7560 B(:,:,14) = -2.0834 -0.1674 -0.0127 -1.3724 -0.7853 0.0141 -1.2462 -2.0874 -1.8179 -0.6612 1.4417 -0.5028 0.7359 0.5513 -0.0937 0.5833 -2.1986 -1.0589 0.2680 1.2708 1.8445 -1.7178 -0.3624 2.5992 2.4769 B(:,:,15) = -1.9915 0.2211 -0.8792 1.7162 -1.1824 1.8791 0.1338 0.1207 0.7979 0.0575 2.6634 -0.9772 -1.4023 1.9158 -2.0530 -3.5620 0.7934 2.8845 3.0420 -0.4115 -2.0293 3.0953 0.7776 0.0454 -0.6836 B(:,:,16) = 0.2460 -0.8852 2.6075 0.4653 0.5208 0.9171 -2.8741 2.2960 -1.6905 -0.0163 0.1987 0.0810 1.4670 -0.0219 3.1898 -1.1416 0.1643 2.6641 3.5801 0.7277 -2.0222 -0.4112 -1.6089 -2.2642 -2.0376 B(:,:,17) = 0.7975 2.9341 0.3443 0.0866 0.5167 0.1475 -3.4558 1.9223 -2.5965 1.4561 -1.4942 -1.1344 0.9004 -0.6161 1.0252 -0.5623 1.3244 -2.1575 -0.8474 -0.6853 -1.4023 -0.5532 -0.4516 -0.5334 3.4513 B(:,:,18) = -2.9338 0.0491 1.8345 2.9347 -1.9308 -0.3876 3.3523 4.0483 0.2978 -0.5219 2.1096 0.3462 0.7005 -1.5934 2.8639 0.4757 -1.7640 -0.7932 2.9646 -0.7123 -1.2909 -1.8976 1.0907 1.8097 -0.5561 B(:,:,19) = 0.5579 0.2422 -2.9485 0.7972 2.5755 1.0189 0.1914 -0.7493 0.6939 -2.0909 -2.5138 2.6576 -1.2495 -0.5541 2.7864 -1.6242 0.5929 -0.1956 0.4622 -3.3564 -0.2555 -1.3294 2.4360 0.0018 0.2349 B(:,:,20) = -2.7642 -0.5471 0.3265 -1.7913 -2.0071 1.3997 0.1897 0.0740 1.5834 0.1635 0.2456 -3.2479 0.7067 -2.1452 0.9359 -1.1186 0.6781 1.9374 0.0016 -1.4852 0.1581 1.1187 -1.2812 1.5271 2.3767 B(:,:,21) = 1.3027 -3.0669 -2.5140 2.5249 0.3256 1.0849 -2.2210 2.2105 1.0322 -2.7332 1.7464 -1.3768 -0.8949 0.7157 1.6362 0.1681 -1.2050 3.8122 0.3636 1.5360 0.5076 1.6824 -1.2537 -0.1030 0.7563 B(:,:,22) = -0.7558 -1.0014 1.8700 1.9205 -0.6140 0.2165 1.6217 -0.8111 1.0028 2.0232 -2.3559 2.7258 1.7126 -1.8611 0.4371 1.6219 0.7750 -2.5612 0.3213 -2.5177 0.1565 -0.5339 -0.5733 -0.2441 -2.5021 B(:,:,23) = 0.9844 0.8369 0.8553 0.2370 1.1270 2.9168 -0.6636 -0.2539 -0.4327 -0.6501 2.1469 1.4433 1.6019 0.9948 0.2525 1.5140 1.5396 0.9000 0.5947 1.4490 1.0458 0.0183 -1.2318 -0.2988 -2.0634 B(:,:,24) = -0.2771 -1.4910 -2.9626 -1.7318 2.2095 0.9512 -1.1338 0.6782 0.7795 -0.8880 -0.8533 -2.7780 -2.3788 -2.0778 0.2766 -0.9914 -0.2575 -0.3793 -0.1217 0.1563 -2.4972 1.8518 -2.1511 1.8243 -0.6004 B(:,:,25) = 0.2687 -0.3347 1.1227 -0.0886 -2.6626 0.9024 -0.8702 -0.0905 -0.3697 0.1555 -2.9463 -1.2182 -1.1932 0.9498 1.0114 0.2617 0.2796 -0.4914 3.5571 -1.1028 -1.6009 -1.5878 1.3678 -1.3583 -2.3621 B(:,:,26) = 1.2563 0.8366 0.8002 0.6838 0.2330 1.1104 -0.0262 -2.4385 0.4708 -1.7288 -0.1345 0.2320 -1.4339 -0.4139 0.7586 1.0655 2.9163 -0.8192 1.4195 0.5019 1.6090 0.7177 0.0177 1.0356 -2.0008 B(:,:,27) = 1.6343 1.0184 0.8376 -0.9728 0.3353 -2.7207 -0.5291 -0.2911 -1.0033 2.2731 -0.7506 0.7822 2.3866 1.6515 -2.9627 -0.4358 -0.4526 3.2547 -2.1035 -2.0407 0.8323 1.2352 -0.3457 1.4855 0.3752 B(:,:,28) = 1.8239 -0.1335 1.4915 -1.0550 -0.5938 3.7806 0.2710 0.9868 -2.0289 -1.1497 -1.0458 0.4945 0.3546 -0.0739 -1.6005 -0.2407 2.5159 -0.2250 0.5005 1.1066 0.2643 -0.0131 1.3026 1.7734 -0.5729 B(:,:,29) = -0.3810 0.8987 -2.2175 -0.4167 0.5621 -0.5270 0.4304 1.0761 0.1885 0.9786 1.7019 1.0872 -0.9485 0.5736 -2.1015 -1.8118 1.4298 -0.1435 0.7297 0.8214 0.2799 -2.1276 0.8208 -0.1314 -3.5065 B(:,:,30) = -0.1133 -2.7520 -3.2753 -1.0057 -0.8834 0.2685 0.9265 2.2004 -0.9980 0.8306 0.0608 0.3621 -1.8136 0.5018 -3.0189 -1.1764 2.5815 0.0425 -2.5444 -1.3692 -1.1503 -0.2703 -1.2848 -0.1888 -1.1203 B(:,:,31) = -0.6610 -0.8840 0.8206 -0.4026 -0.1174 0.9512 2.4037 1.1887 2.1854 0.1708 1.4476 -1.4069 -2.0353 -2.0397 4.2878 -2.4774 -0.8173 -2.1959 -2.1793 -0.7268 1.2948 0.3052 2.3863 -1.2332 -1.6261 B(:,:,32) = -0.4802 -0.6304 -2.3091 -0.7794 1.3444 2.2289 0.2194 1.5060 0.0024 1.3949 -1.2486 -0.4703 2.1090 0.6853 -1.4494 5.4418 -1.3608 2.3341 -0.5118 5.2558 1.0397 1.5947 -1.6032 -3.4416 2.3021 B(:,:,33) = -1.9845 0.9943 1.9642 -0.4459 0.8147 1.7308 -3.0916 -3.4756 3.4416 4.2824 -1.0330 3.4350 -3.7624 1.5342 -0.7833 -1.1288 0.0081 -2.4436 -2.2191 -1.0281 0.3592 -1.9227 -1.7233 0.3510 1.2419
  2 个评论
Image Analyst
Image Analyst 2022-8-16
To make it more general and robust, you'd do
A = randn(5, 5, 99);
[rows, columns, slices] = size(A)
B = zeros(rows, columns, slices/3);
for k = 1 : slices/3 % or 1 : size(B, 3)
B(:, :, k) = sum(A(:, :, (k - 1) * 3 + (1 : 3)), 3);
end
whos
B
We don't recommend using i (the imaginary variable) as a loop counter, and it's more robust to preallocate the size of B based on the size of A. You might also check in advance if the number of slices is not a multiple of 3 and throw up a friendlier error if it's not.

请先登录,再进行评论。

更多回答(1 个)

Image Analyst
Image Analyst 2022-8-16
OK, so go ahead. I know you did not actually ask a question, but this is how you must proceed.
sum1 = (A1+A2+A3) ;
sum2 = (A4+A5+A6);
% Etc
sum33 = (A97+A98+A99);
Yes, you'll have 33 lines of code rather than a small, compact for loop, but that is the penalty you must pay for unwisely having 99 individual, separately named variables instead of having a higher dimensional array.
  3 个评论
Image Analyst
Image Analyst 2022-8-16
编辑:Image Analyst 2022-8-16
If you have a 3-D array, like you should rather than separately named variables, you can do this:
[rows, columns, slices] = size(A)
sums = zeros(rows, columns, slices/3, class(A));
slice = 1;
for k = 1 : 3 : slices
sums(:, :, slice) = sum(A(:, :, k : k+2), 3);
slice = slice + 1;
end

请先登录,再进行评论。

类别

Help CenterFile Exchange 中查找有关 Operating on Diagonal Matrices 的更多信息

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by