normalise a column in a matrix

2020 12 6
1 个回答
更新时间：2020 12 6
11 次查看（30 天）

0 个投票

I have a 5x10 matrix of non-zero values. How can I normalise the 9'th column and make all its values equal to 1.

请先登录，再回答此问题。

回答（1 个）

Cris LaPierre
Cris LaPierre 2020-12-6
Ran in:

0 个投票

Ran in:
Normalize and making all its values equal 1 are two different, non-equivalent processes.
Assuming you want to set all values to 1, something like this should work:
% Create 5x10 matrix
m=rand(5,10);
% Set all values in the 9th column equal to 1
m(:,9)=1
m = 5×10
0.0140 0.6808 0.8513 0.3171 0.7192 0.0997 0.3669 0.9666 1.0000 0.3060 0.6399 0.8033 0.3665 0.9091 0.0736 0.3212 0.0721 0.8504 1.0000 0.0836 0.9530 0.8310 0.2890 0.7311 0.5017 0.7145 0.7677 0.2626 1.0000 0.5972 0.9194 0.2587 0.6253 0.5791 0.0637 0.3085 0.7832 0.5275 1.0000 0.9422 0.1942 0.1323 0.8923 0.1072 0.5695 0.4803 0.0237 0.6503 1.0000 0.3719
●

2 个评论
显示 无 隐藏 无

Fadi Lama
Fadi Lama 2020-12-6
I want to normalize the column so that all its values are equal to one if that makes sense
(I was thinking of dividing each row by the value in the 9th column but was looking for something simpler)
Cris LaPierre
Cris LaPierre 2020-12-6
Ran in:
Ran in:
Ok, but the effect would be the same, right?
Divide column 9 by itself.
% Create 5x10 matrix
m=rand(5,10);
% Normalize each value in column 9 by dividing by itself
m(:,9)=m(:,9)./m(:,9)
m = 5×10
0.2220 0.3633 0.2327 0.0752 0.2392 0.0317 0.2442 0.3519 1.0000 0.7160 0.5693 0.1504 0.6034 0.5271 0.7093 0.1267 0.3073 0.8678 1.0000 0.9064 0.7947 0.9117 0.4383 0.6368 0.9732 0.0727 0.4674 0.7977 1.0000 0.9629 0.0800 0.7259 0.5368 0.5817 0.3788 0.1339 0.5561 0.0655 1.0000 0.4742 0.3518 0.1036 0.2013 0.5821 0.3154 0.0541 0.5438 0.1723 1.0000 0.4470
●
btw, normalizing each row by the value that is in its column 9 is just as easy
m2=rand(5,10);
m2=m2./m2(:,9)
m2 = 5×10
0.9815 0.2271 0.2902 0.1020 0.5926 1.0735 0.3889 0.0205 1.0000 0.4472 0.7600 0.5928 0.8442 1.0917 1.2915 0.7797 0.7137 0.8735 1.0000 0.3898 16.0345 13.7806 6.8526 20.2673 1.9944 13.3427 14.5061 5.6493 1.0000 4.1880 0.0475 0.7783 0.9273 1.0538 1.0699 0.7781 0.6793 0.4814 1.0000 1.1109 0.2156 0.8290 0.1595 0.7077 0.0473 0.7178 0.6384 0.3150 1.0000 1.0240
●

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Mathematics 的更多信息

标签

Community Treasure Hunt

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

Start Hunting!

Translated by