How do I find the rows in one table that have certain string?
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I have a Table with 80,000 rows and 19 variables lets call it T, in column 17 I have the STATUS of the products, i.e., 'Active', 'Inactive', or 'Other'.
I want to identify the rows in column 17 that contain 'Inactive' so I can eventually delete these form the original table.
I have used the following code but it separates the rows containing 'Inactive' it does not identify the row number
[rows]=T(strcmp(T.STATUS,'Inactive'),:);
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Voss
2023년 8월 1일
편집: Voss
2023년 8월 1일
"I want to identify the rows in column 17 that contain 'Inactive'"
% get the indicies of rows with "Inactive" STATUS:
inactive_rows = find(strcmp(T.STATUS,'Inactive'));
"so I can eventually delete these form the original table"
% delete them from T:
T(inactive_rows,:) = [];
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dpb
2023년 8월 1일
T.STATUS=categorical(T.STATUS); % more efficient for categorical-type variables
isInact=(T.STATUS=="Inactive"); % logical vector of inactive
Use the far more efficient logical indexing vector; you don't need to find() the row number explicitly at all for this purpose. It's not terribly often that actually do need to have the row number itself although find will do so, avoid using it until you do find (so to speak) a real problem you can't solve otherwise.
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dpb
2023년 8월 1일
편집: dpb
2023년 8월 1일
Use the logical addressing vector, of course...two choices, either
T.STATUS(isInact,:)=[];
delete the inactive rows, or
T=T(T.STATUS(~isInact,:));
keep everything that is NOT inactive...
If this is new to you, see <array-indexing> in the doc; some time spent in the <Getting Started> language fundamentals section on basic MATLAB syntax and operations would provide a pretty high return on the investment. There's also the OnRamp video course if you're more attuned to that sort of thing.
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