How to modify a list of filenames in a specific way?

Dear Matlab community,

I have a fairly simple question for you experts. I'd like make a column taking just the first part of a file name (string):

e.g. This is what I have

names =

"vul1_4_9.txt"

"bat1_1_1.txt"

"chy1_1_16.txt"

"chy1_1_17.txt"

"g6_1_18.txt"

"stcv1_1_1.txt"

"ser1_3_4.txt"

And I'd like to have instead a column just with the names before the first "_" :

names=

"vul1"

"bat1"

"chy1"

"chy1"

"g6"

"stcv1"

"ser1"

So far, I was able to "substract" the ".txt" part of the file name using the following loop:

names_n = length(names)
for id = 1:names_n
    [~, f,ext] = fileparts(names(id));
    rename = strcat(f - '_*_*') ;
    names_new = [names_new;rename] 
end

Obtaining this output:

names_new=

"vul1_4_9"

"bat1_1_1"

"chy1_1_16"

"chy1_1_17"

"g6_1_18"

"stcv1_1_1"

"ser1_3_4"

How should I proceed?

[Amanda]

Thank you SO much!

Answer 1

[Stephen23]

S = ["vul1_4_9.txt"
    "bat1_1_1.txt"
    "chy1_1_16.txt"
    "chy1_1_17.txt"
    "g6_1_18.txt"
    "stcv1_1_1.txt"
    "ser1_3_4.txt"];
Z = extractBefore(S,'_')

Z = 7×1 string array
    "vul1"
    "bat1"
    "chy1"
    "chy1"
    "g6"
    "stcv1"
    "ser1"