How to read data from a CSV into a column vector

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I have 25 csv files that I need to grab data from, they are all in the same format with no headers, I would like to grab all of this data, and store it into a column vector. Previous iterations of this program have used fread(filename, size) to read binary files into a column vector and throw them into a calculation script, I would like to keep the script in the same format so I need to read this csv data into a Column Vector.
I also imported them into a table so if there is a way to convert this table into a Column vector that works too, I am not concerned with the loss of efficiency in terms of runtiime.

Answers (1)

Monika Jaskolka
Monika Jaskolka on 5 Nov 2020
Edited: Monika Jaskolka on 5 Nov 2020
>> m = readmatrix('test.csv')
m =
1 2 3 4
5 6 7 8
>> m = m(:)
m =
1
5
2
6
3
7
4
8
For mixed data:
>> m = readtable('test.csv')
m =
2×4 table
Var1 Var2 Var3 Var4
____ ____ _____ ____
1 2 {'a'} 4
5 6 {'b'} 8
>> m = table2cell(m)
m =
2×4 cell array
{[1]} {[2]} {'a'} {[4]}
{[5]} {[6]} {'b'} {[8]}
>> m = m(:)
m =
8×1 cell array
{[1]}
{[5]}
{[2]}
{[6]}
{'a'}
{'b'}
{[4]}
{[8]}
  4 Comments
waleed khalid
waleed khalid on 5 Nov 2020
Thanks for that! For some reason, when I call readmatrix(filename), the values in my csv's become obfuscated to this:
0.0000 0.0000 0.0000 -0.0000 0.0002 0.0000
0.0000 0.0000 0.0000 -0.0000 0.0002 0.0000
0.0000 0.0000 0.0000 -0.0000 0.0002 0.0000
0.0000 0.0000 0.0000 -0.0000 0.0002 0.0000
0.0000 0.0000 0.0000 -0.0000 0.0002 0.0000
Monika Jaskolka
Monika Jaskolka on 5 Nov 2020
The data is there, but Matlab has different formats for displaying data in the Command Window. Read more about it here: https://www.mathworks.com/help/matlab/ref/format.html . The default is "format short", which is only 4 decimal places.
So if you want to see more decimals, type in "format long" into your Command Window, and then try to display the matrix again.

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