Removing zeros from a binary array if length of zeros is lesser than a value

Question

Meghana Balasubramanian 2020-2-19

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/506315-removing-zeros-from-a-binary-array-if-length-of-zeros-is-lesser-than-a-value

评论： Meghana Balasubramanian 2020-2-19

采纳的回答： KSSV

Hello,

I have an array:

input = [0;0;0;0;0;0;0;1;0;1;1;1;0;0;0;0;0;0;1;1;0;0;0;0]

I would like to remove only the 0's between the 1's if the stretch of 0's is lesser than 5, between the 1's. So, for this instance, the output would look something like:

output = [0;0;0;0;0;0;0;1;1;1;1;0;0;0;0;0;0;1;1;0;0;0;0].

Any help would be appreciated.

Thanks!

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

KSSV 2020-2-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/506315-removing-zeros-from-a-binary-array-if-length-of-zeros-is-lesser-than-a-value#answer_416283

在 MATLAB Online 中打开

input = [0;0;0;0;0;0;0;1;0;1;1;1;0;0;0;0;0;0;1;1;0;0;0;0] ; 
idx = input==1;  % get the locations of 1 
% split zeros and one's into cell 
idr = diff(find([1;diff(idx);1]));
D = mat2cell(input,idr(:),size(input,2));
% get the lengths of each cell 
L = cellfun(@length,D) ; 
L(2:2:end) = NaN ; % make length of 1's NaN as it is not needed 
% get the length of zeros which are less then 4 
id = L<4 ; 
% remove those zeros 
D(id) = [] ; 
% convert to matrix 
output = cell2mat(D) ; 

5 个评论
显示 3更早的评论隐藏 3更早的评论

Stephen23 2020-2-19

在 MATLAB Online 中打开

The RHS would need to be a scalar cell array:

D(id) = {1};

Meghana Balasubramanian 2020-2-19

Stephen,

Some of the cells have zeros of varying lengths. Replacing it with {1} would simply reduce the entire cell content to 1. Should I run a for loop to find and replace the zero's between the 1's using values stored in "L = cellfun(@length,D);" ?

请先登录，再进行评论。

Answer 2

Raymond MacNeil 2020-2-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/506315-removing-zeros-from-a-binary-array-if-length-of-zeros-is-lesser-than-a-value#answer_416286

在 MATLAB Online 中打开

k = [0;0;0;0;0;0;0;1;0;1;1;1;0;0;0;0;0;0;1;1;0;0;0;0];
y = regexp(num2str(k)', '(?<=[0]{5,})0*', 'split');
z = strjoin(cellfun(@(x) replace(x, '', ' '), y, 'UniformOutput', false));
out = str2num(z)';

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Raymond MacNeil 2020-2-19

编辑：Raymond MacNeil 2020-2-19

Could also use regexprep. I realize I added more steps than was necessary. Also, other ways exist that don't require regexp. This just happened to be the first solution that came to mind.

请先登录，再进行评论。