Extract, save, plot three specific columns from huge txt file

Hi,

I meet a problem about extracting columns from a huge txt file, and what I want is using textscan to extract column 1, 3 and 8 as a new txt file. Then I try to plot them in subplot, the column 1 as x axis and column 3 and 8 become y1 and y2. However, I ended up with error:

Index in position 1 exceeds array bounds (must not exceed 1)

I understand that Matlab treat the whole file as one column, anyone could help me with some codes please? Thank you very much.

Answer 1

[KALYAN ACHARJYA]

Any issue?

data=readmatrix('test.txt');

Now Extract the clolumns as

data(:,2); % For 2nd Column
data(:,3); % For 3rd Column
....so on
plot(...)

[LuYao Guo]

Hi Sir, first of all, thank you for answering. Unfortunately I fail to use readmatrix. And I realize the last three columns involves 'E' '-' and time, are they the reasons causing the error?

[KALYAN ACHARJYA]

Please see readtable

https://in.mathworks.com/help/matlab/ref/readtable.html