How do I modify the given code to work on specific trials containing a specific key string?

Hey all! I'm working on a project where I am analysing data from a .mat file. The file in question contains information for a specific number of trials from the experiment, where each trial is for a different image from a database, represented by a key. All the keys for a file are present in the following class "d.meta.image.filename" and I can retrieve said information about the keys using the following command.

tmp = d.meta.image.filename('time',Inf).data;

which gives tmp as a 1 x n cell array. Each cell contains a 1 x 1 struct with the relevant information as shown below:

key    'cps201410017278'
meta   1x1 struct
ppm    '/home/marmolab/UT Natural Images/Human Made Scene Collection - Set 1/cps201410067326.ppm'
exif   '/home/marmolab/UT Natural Images/Human Made Scene Collection - Set 1/exif/cps201410017278.exif'

How do I go about selecting all possible trials in a file, for one specific key? I'm thinking somehing like

myTrials = find(keys == tmp('cps201410017278')) 

after defining tmp as above. Thanks in advance!

Answer 1

[Walter Roberson]

keys = cellfun(@(C) C.key, tmp, 'uniform', 0);
matches = strcmp(keys, 'cps201410017278');

tmp_subset = tmp(matches);

[Kevin Akash Rajasekaran]

Cool. This works! Thanks bunches!