how to compare last n characters of many strings in matlab?

I have a huge number strings stored in cell named 'b'. some names of the signals inside this cell looks like this 'PECCalc_tqElFil2_VW_173', 'PECCtl_bDampCtl_VW_173', 'PECCtl_uDstRipplNrm_VW_171', 'PEC_kWaaDkMEoacAcF33ry86TG5B0BRjIXWbgnK1vt1D2Gc_171', 'time_152', 'time_173',

then I use string compare to get only signals starting with the name PEC using the following.

 matcontent = load('w50_2_2.mat'); 
usefield = strncmpi(fieldnames(matcontent),'PEC',3);
b = fieldnames(matcontent);
matcontent_cell = struct2cell(matcontent);
selectedvariables = matcontent_cell(usefield);

so selectedvariables has all the signals starting only with PEC.

Similarly I want to filter out all the signals ending with _173. How do I do this? How can I use string compare to compare last n characters and segregate those signals? the length of these signals also vary. Please help me! Thanks in advance.

Answer 1

[Stephen23]

Use regexp, you can wrap it in a cellfun call to get the indices:

C = {...
    'PECCalc_tqElFil2_VW_173'
    'PECCtl_bDampCtl_VW_173'
    'PECCtl_uDstRipplNrm_VW_171'
    'PEC_kWaaDkMEoacAcF33ry86TG5B0BRjIXWbgnK1vt1D2Gc_171'
    'time_152'
    'time_173'
    }
fun = @(str,pat)~cellfun('isempty',regexp(str,pat,'once'));
idxPEC = fun(C,'^PEC')
idx173 = fun(C,'\_173$')

returns these indices:

idxPEC =
     1
     1
     1
     1
     0
     0
idx173 =
     1
     1
     0
     0
     0
     1

[Tejaswini Ramesh]

this works! thank you very much :)

[Tejaswini Ramesh]

please also tell me how to get all the names of the signals when idx173 or idxPEC value is 1. Thank you!

[Stephen23]

Using very basic array indexing:

 C(idxPEC | idx173)