How to delete multiple rows from a table using a for loop (with a condition)?

2021 9 2
1 个回答
回答已采纳
更新时间：2021 9 3
3 次查看（30 天）

0 个投票

I would like to delete multiple rows form a table (imported from Excel).
I have "n" number of rows with 5 columns (Var1,..........,Var5). Now if in column 5 (Var5), there is value greater than 0, I want that row and the next three rows to be deleted.

请先登录，再回答此问题。

 采纳的回答

Jeremy Hughes
Jeremy Hughes 2021-9-2
Ran in:

0 个投票

Ran in:
I wouldn't use a for loop. MATLAB excells at array operations.
A = randn(12,5); % Make some data with positive and negative values
A(1:4:5) = -abs(A(1:4:5));
A(end-4:end) = -abs(A(end-4:end));
T = array2table(A)
T = 12×5 table
A1 A2 A3 A4 A5 _________ ________ ________ ________ ________ -0.18657 0.76498 0.23522 -0.86791 0.35787 0.74813 0.73723 -0.13228 0.05872 -1.1772 1.4034 -1.6129 -0.55285 2.2033 0.20268 0.91163 0.915 -1.3487 -0.31358 0.16887 -1.3759 1.4728 0.98564 -1.0473 0.34148 -0.68973 -0.28485 -0.98694 0.29496 1.4129 2.4566 -0.9063 -1.3356 -1.1073 2.1731 -0.068694 -0.3263 0.90646 -0.19821 -1.1389 1.1861 1.0306 3.1811 -2.0224 -0.60713 -0.044051 -0.62426 0.72973 -0.58808 -0.66111 0.46205 0.12273 1.0989 0.013466 -1.363 -0.63828 0.81857 -0.54734 0.59388 -0.76208
rowIdx = find(T.A5 > 0);
rowIdx = rowIdx(:) + (0:3); % expands column + row
T(rowIdx,:) = [] % deletion
T = 2×5 table
A1 A2 A3 A4 A5 ________ _______ ________ ________ ________ 0.46205 0.12273 1.0989 0.013466 -1.363 -0.63828 0.81857 -0.54734 0.59388 -0.76208
You can also only check every fourth row, but there's some tricky math.
rowIdx = find(T.A5(1:4:end) > 0) % check every 4th entry will result in the "block" index though
rowIdx = 4*(rowIdx-1)+1; % re-align to the right places in the original array
rowIdx = rowIdx(:) + (0:3); % expands column + row
T(rowIdx,:) = [] % deletion
T = 2×5 table
A1 A2 A3 A4 A5 ________ _______ ________ ________ ________ 0.46205 0.12273 1.0989 0.013466 -1.363 -0.63828 0.81857 -0.54734 0.59388 -0.76208

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Data Import from MATLAB 的更多信息

产品

版本

R2018a

标签

Community Treasure Hunt

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

Start Hunting!

Translated by