find element egual to substring in array string

c=["A1_asd";"A2_rrd";"A_dj";"B1_gre";"B2_rffe";"B3_rffe"]

c = 6×1 string array
    "A1_asd"
    "A2_rrd"
    "A_dj"
    "B1_gre"
    "B2_rffe"
    "B3_rffe"

%i want to catch string before letter_ and search member

%find all member egual to  A in c;
%find all member egual to  B in c;

result:

["A1_asd";"A2_rrd";"A_dj"]

["B1_gre";"B2_rffe";"B3_rffe"]

Answer 1

[Dyuman Joshi]

From what I understood of the given information -

%Input
c=["A1_asd";"A2_rrd";"A_dj";"B1_gre";"B2_rffe";"B3_rffe"]

c = 6×1 string array
    "A1_asd"
    "A2_rrd"
    "A_dj"
    "B1_gre"
    "B2_rffe"
    "B3_rffe"

%Output
a = c(startsWith(c, 'A'))

a = 3×1 string array
    "A1_asd"
    "A2_rrd"
    "A_dj"

b = c(startsWith(c, 'B'))

b = 3×1 string array
    "B1_gre"
    "B2_rffe"
    "B3_rffe"