# Import data from txt file in to a 2D array

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Cosimo Mercuro on 29 Jan 2021
Commented: Cosimo Mercuro on 31 Jan 2021
Hi.
I've this txt file:
I'd like that all number (32) that are between the square barckets will be the first rows of a 2D array (matrix) 24x32 .
Anything like this:
Any idea?

Scott Ronquist on 29 Jan 2021
Hello Cosimo,
I understand you are trying to import the data stored in "acquisizione2-new.txt" into the MATLAB Workspace. This is possible with the Name-Value Pair Arguments available for the readtable function. After importing the data, there is one extra step that is necessary to remove NaN columns in the table output from readtable.
Please try the code given below, hope this helps!
'Delimiter',[" ","]","["], 'LineEnding', "]\n",'TrimNonNumeric',true);
% find NaN columns
nanIdx = arrayfun(@(x) all(isnan(data{:,x})), 1:width(data));
% remove NaN columns
data(:,nanIdx) = [];
% convert to numeric array (optional)
dataMatrix = data{:,:};
##### 3 CommentsShow 1 older commentHide 1 older comment
Scott Ronquist on 30 Jan 2021
Hi Cosimo,
The output of readtable is a table variable. The values within tables can be accessd in many ways, see this summary table for more details. One of the ways to access the values of a table is to use curly brackets ("{ }"). Using curly brackets on table variables means "extract data and concatenate". Within the curly brackets you must specify 2 things: {rows, columns}. Using a colon, ":", means "all". so "{:,:}" means "extract all rows and columns and concatenate".
A more clear alternative would be to use the table2array function. Using the variables previously defined, note that the following are equivalent:
>> a = data{:,:};
>> b = table2array(data);
>> isequal(a,b)
ans =
logical
1
Cosimo Mercuro on 31 Jan 2021
Many thanks.

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