清空筛选条件
清空筛选条件

Finding mean of matrix excluding 0

49 次查看（过去 30 天）
goyanks1989
goyanks1989 2016-5-13
评论： Image Analyst 2016-5-13
I have a 4 1200x1200 matrixes which includes numerous 0 values, lets just call them 'a' 'b' 'c' and 'd'
How do i find the mean of each individual point in the matrix (that is a+b+c+d), while ignoring the 0 values?
Thank you for the help!

请先登录，再回答此问题。

采纳的回答

Star Strider
Star Strider 2016-5-13
If I understand correctly what you want to do, this will work:
a = randi([0 5], 10);
b = randi([0 5], 10);
c = randi([0 5], 10);
d = randi([0 5], 10);
abcd = cat(3, a, b, c, d); % Concatenate Along 3rd Dimension
abcd(abcd == 0) = NaN; % Set Zeros To ‘NaN’
mean_abcd = mean(abcd, 3, 'omitnan'); % Use 'omitnan' Argument And Take ‘mean’ Across 3rd Dimension

更多回答（1 个）

Image Analyst
Image Analyst 2016-5-13
You mean the mean at each location, like (a+b+c+d)/(# non-zeros)? How about
counts = (a~=0) + (b~=0) + (c~=0) + (d~=0);
theMeans = (a+b+c+d) ./ counts;
theMeans is a 1200-by-1200 matrix where each value is the mean of up to 4 values. If all 4 values are 0 then the value there is a nan.
  2 个评论
goyanks1989
goyanks1989 2016-5-13
Thank you for the answer. When I run my code I receive this error message
Error using ./
Integers can only be combined with integers of the same class, or scalar doubles
is this because my matrix is a 1200x1200 uint16? (and i am not exactly sure what uint16 means)
Image Analyst
Image Analyst 2016-5-13
They are not all uint16 - some must be different. Cast all to double and then do it.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Creating and Concatenating Matrices 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