How to Delete Non-Numeric Columns from Table

I'm using readtable to load data from a text file. Some columns have text in them; others don't. I want to effectively delete the columns that have at least one entry of non-numeric data, so that I can convert the remaining table to an array (using table2array).

How can I do this?

[Andrew Reibold]

Can you please provide an example of the readtable output? :-)

Answer 1

[Arun Mathew Iype]

I think it is better to use the “Import Data” tool which allows you to import data as an array directly using a GUI and also to generate scripts for doing the same everytime.

http://www.mathworks.com/help/releases/R2014a/matlab/import_export/import-data-interactively.html

However to answer your question the following steps and example should be helpful.

1. Create a TEXT file called “sampledata.txt” and copy the following data into it.

LastName,Gender,Age,Height,Weight,Smoker Smith,M,38,71,176,1 Johnson,M,43,69,163,0 Williams,F,38,64,131,0 Jones,F,S,67,133,0 Brown,F,49,64,119,0

1. Run the below script to delete the columns which have text in them and generate the required array. Note that if even one item in a column is a string then the whole column is of cell array

% read the data into  a variable
T = readtable('sampledata.txt')
V = T.Properties.VariableNames;
for i = [1:width(T)]
    v_is_cell(i) = iscell(T.(V{i}));
end
%use logical indexing to delete the required columns
T(:,v_is_cell) = [];
table2array(T)

T =

     LastName     Gender    Age     Height    Weight    Smoker
    __________    ______    ____    ______    ______    ______

    'Smith'       'M'       '38'    71        176       1     
    'Johnson'     'M'       '43'    69        163       0     
    'Williams'    'F'       '38'    64        131       0     
    'Jones'       'F'       'S'     67        133       0     
    'Brown'       'F'       '49'    64        119       0

ans =

    71   176     1
    69   163     0
    64   131     0
    67   133     0
    64   119     0

[Kevin]

This is what I was looking for. Thanks!