Place filenames with common pattern in a cell array

Hi there,

If I have a cell array containing filenames in the following format 'breakpoint_b40_f15.txt', 'breakpoint_b50_f15.txt', 'breakpoint_b40_f20.txt', 'breakpoint_b50_f20.txt', how do I create a new cell array where each row contains the files with the same number after 'f'? for example. 'breakpoint_b40_f15.txt' and 'breakpoint_b50_f15.txt' should be in the same row, and 'breakpoint_b40_f20.txt' and 'breakpoint_b50_f20.txt' should be in the same row but in a different row to the f15 row.

Many thanks

[Stephen23]

C = {'breakpoint_b40_f15.txt', 'breakpoint_b50_f15.txt', 'breakpoint_b40_f20.txt', 'breakpoint_b50_f20.txt'};
D = reshape(C,2,2).'

D = 2×2 cell array
    {'breakpoint_b40_f15.txt'}    {'breakpoint_b50_f15.txt'}
    {'breakpoint_b40_f20.txt'}    {'breakpoint_b50_f20.txt'}

[Davindra Usov]

Thanks a bunch Stephen. This works but how can I change the number of rows of D to be the number of unique f values, which in this case is 2 (15 and 20)?

Answer 1

[dpb]

C = {'breakpoint_b40_f15.txt', 'breakpoint_b50_f15.txt', 'breakpoint_b40_f20.txt', 'breakpoint_b50_f20.txt', 'breakpoint_b40_f25.txt','breakpoint_b50_f25.txt'};
N=numel(unique(extractBetween(extractAfter(C,'breakpoint_'),'_','.txt')));
reshape(C,[],N).'

Relies upon the sequence being already sorted in pairs; otherwise need to locate the elements position if not already sorted -- or sort first by the second substring of interest. Another case where putting metadata into the filenames makes things harder than if were real data in a database file....seems to be a spate of those recently.

[Davindra Usov]

This worked a charm, cheers!!

Answer 2

[dpb]

C = {'breakpoint_b40_f15.txt', 'breakpoint_b50_f15.txt', 'breakpoint_b40_f20.txt', 'breakpoint_b50_f20.txt'}.';
N=(extractBetween(extractAfter(C,'breakpoint_'),'_','.txt'))

N = 4×1 cell array
    {'f15'}
    {'f15'}
    {'f20'}
    {'f20'}

uN=unique(N)

uN = 2×1 cell array
    {'f15'}
    {'f20'}

Add/use N as a grouping variable or sort by indexing array...

Answer 3

[Kevin Holly]

C = {'breakpoint_b40_f15.txt', 'breakpoint_b50_f15.txt', 'breakpoint_b40_f20.txt', 'breakpoint_b50_f20.txt', 'breakpoint_b40_f25.txt','breakpoint_b50_f25.txt'};
D = strfind(C,'breakpoint_b40_f');
f = length([D{:}])

f = 3

D = strfind(C,'_f15');
b = length([D{:}])

b = 2

D = reshape(C,b,f).'

D = 3×2 cell array
    {'breakpoint_b40_f15.txt'}    {'breakpoint_b50_f15.txt'}
    {'breakpoint_b40_f20.txt'}    {'breakpoint_b50_f20.txt'}
    {'breakpoint_b40_f25.txt'}    {'breakpoint_b50_f25.txt'}

[Davindra Usov]

thanks!