How do I determine which pattern is in a string?

Hi,

I have a table imported from Excel which contains the units of measurement within the Variable Names of the table properties, i.e.

MyTable.Properties.VariableNames = 1x 5 cell array

{'Node Number'} {'X Location (m)'} {'Y Location (m)'} {'Z Location (m)'} {'Normal Stress (Pa)'}

I'm trying to determine which units have been used in the Variable Names from a given list, pat = ["(m)", "(cm)", "(mm)", "(in)", "(ft)"] ;

So far I've tried functions such as contains and strcmp but that's only told me which cells of my variable names contain one of the given patterns, rather than which pattern. Is there a way to do this without having to use contains a separate time for each variable.

Thanks,

Nathan.

Answer 1

[Star Strider]

I am not certain what result you want.

Try this:

MyTable.Properties.VariableNames = {{'Node Number'}    {'X Location (m)'}    {'Y Location (m)'}    {'Z Location (m)'}    {'Normal Stress (Pa)'}};
Outc = regexp([MyTable.Properties.VariableNames{:}], '\(\w*\)','match')
Out = [Outc{:}]

producing:

Out =

  1×4 cell array

    {'(m)'}    {'(m)'}    {'(m)'}    {'(Pa)'}

EDIT — (31 Mar 2021 at 15:52)

Another option:

Out = extractBetween([MyTable.Properties.VariableNames{2:end}], '(',')')

producing:

Out =

  1×4 cell array

    {'m'}    {'m'}    {'m'}    {'Pa'}

The extractBetween function was introduced in R2016b.

[Nathan O'Donoghue]

Hi Star Strider

Thanks for such a swift response, apologies for the delay in mine, I hope that you had a great weekend.

That first solution is ideal thank you! From there I'll be adding on something like:

Index = find(contains(pat, Outc(1)));

switch Index
    case 2
        %Convert from cm to m
        
    case 3
        %Convert from mm to m
        
    case 4 
        %Convert from in to m
        
    case 5
        %Convert from ft to m
end

Thanks again and all the best,

Nathan.

[Star Strider]

As always, my pleasure!

No worries about the delay — the longest time between my posting an Answer and the original poster accepting it (that I can document) was 1866 days. (I kept track of that out of my own curiosity.)

[Nathan O'Donoghue]

Oh wow!

[Star Strider]

Definitely!