error in std for 3d matrix

1 ビュー (過去 30 日間)
Anastasia
Anastasia 2016 年 12 月 12 日
コメント済み: Guillaume 2016 年 12 月 13 日
Hey guys!
I am trying to find the std of a 3D matrix, where size(X) is 207 x 201 x 34. Since I must reshape to find std, I am using this formula: std(reshape(X,1,207*201*34)).
And I obtain this error: Error in std (line 31) y = sqrt(var(varargin{:}));
When I look at the syntax, I thought of using std(reshape(X,1,207*201*34), 0, 3), where 3 is for 3D, however I still obtain the same error.
What I am missing?
Thank you very much in advance!
  2 件のコメント
Anastasia
Anastasia 2016 年 12 月 13 日
編集済み: Anastasia 2016 年 12 月 13 日
Hello, this is the full text of the error message:
Error using var (line 58) First argument must be single or double.
Error in std (line 31) y = sqrt(var(varargin{:}));
Error in Code3D (line 27) th=mean(mean(mean(X))) + std(reshape(X,1,207*201*34));
Is the problem that X is nor single nor double, but 207*201*34? How can I fix that?
Thank you!

サインインしてコメントする。

回答 (2 件)

Isabella Osetinsky-Tzidaki
Isabella Osetinsky-Tzidaki 2016 年 12 月 12 日
try std(x(:))
  1 件のコメント
Anastasia
Anastasia 2016 年 12 月 13 日
Hello! Thank you for your answer but I obtain the same error...

サインインしてコメントする。


Guillaume
Guillaume 2016 年 12 月 13 日
Error: First argument must be single or double
Well, clearly, your first argument (a transform of X) is not single or double. So what is:
class(X)
If it's an integer type:
Xdouble = double(X);
th = mean(Xdouble(:)) + std(Xdouble(:));
  2 件のコメント
Guillaume
Guillaume 2016 年 12 月 13 日
Without context it's impossible to say if it's correct or not. Certainly, if you want the standard deviation of your integers, you have to convert them to double. If an integer result is then required, you can convert the output back to uint16 (with the loss of precision that it entails).

サインインしてコメントする。

カテゴリ

Find more on Numeric Types in Help Center and File Exchange

タグ

Community Treasure Hunt

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

Start Hunting!

Translated by