I want to retrieve columns where the subtype row has values that start with "1".
library(data.table)
df.1 <- df[df["subtype",] %like% "1",]
Data:
> dput(df[1:10,1:10])
structure(list(TCGA.2Z.A9J1.01A = c("1a", "5.13553076559331",
"5.25437106109279", "0", "6.94770472476424", "0", "12.413916703553",
"11.192440344074", "3.1585955515009", "0"), TCGA.2Z.A9J3.01A = c("2a",
"4.75608390849743", "3.47688712558277", "3.69415587836022", "7.55464180068354",
"0", "10.1701864662239", "9.9698319970815", "5.3250949389428",
"0"), TCGA.2Z.A9J6.01A = c("2b", "5.17761487414502", "6.65033806253549",
"0.584770128557275", "6.94039112615504", "0", "12.0370627256659",
"10.8210532515207", "5.53845435576078", "0"), TCGA.2Z.A9J8.01A = c("1b",
"3.73015082384196", "5.42861476811507", "0", "7.92705080275384",
"0.41565051441473", "11.9979504885468", "9.91529337032864", "5.14529839229733",
"0"), TCGA.2Z.A9JD.01A = c("2a", "3.30975827142464", "4.33563331445214",
"0", "8.67290934153811", "0", "10.9513709097776", "10.8023152138843",
"1.84534953815009", "0"), TCGA.2Z.A9JG.01A = c("2c", "7.28850529763777",
"3.84460660023553", "3.00626211318484", "5.81778440061722", "0",
"12.0868373610296", "10.3281796591297", "3.6562103201826", "0"
), TCGA.2Z.A9JJ.01A = c("1c", "6.28339584818368", "0.807272479985472",
"4.53120676686483", "6.40832124805635", "0", "12.8200019062179",
"11.792050825269", "2.35741124701605", "0"), TCGA.2Z.A9JL.01A = c("1c",
"7.03644948442735", "3.73611776175452", "1.34522603534256", "6.5525507570889",
"0.597983993789946", "12.9645888051835", "11.0094140803487",
"7.40469964993127", "0"), TCGA.2Z.A9JN.01A = c("1b", "4.17567628766862",
"0", "0", "7.2921559549592", "0", "12.2914311784018", "10.8173916627083",
"0.514097004894233", "0"), TCGA.2Z.A9JP.01A = c("1d", "6.3033314339384",
"1.11789447981141", "1.74010724619747", "7.46591652705797", "0",
"13.3435017632051", "11.2086677724798", "1.74010724619747", "0"
)), row.names = c("subtype", "A1BG", "A1CF", "A2BP1", "A2LD1",
"A2ML1", "A2M", "A4GALT", "A4GNT", "AAA1"), class = "data.frame")
>Solution :
We may need to use the logical index as column index instead of row index
df[,df["subtype",] %like% "1"]
-output
TCGA.2Z.A9J1.01A TCGA.2Z.A9J8.01A TCGA.2Z.A9JJ.01A TCGA.2Z.A9JL.01A TCGA.2Z.A9JN.01A TCGA.2Z.A9JP.01A
subtype 1a 1b 1c 1c 1b 1d
A1BG 5.13553076559331 3.73015082384196 6.28339584818368 7.03644948442735 4.17567628766862 6.3033314339384
A1CF 5.25437106109279 5.42861476811507 0.807272479985472 3.73611776175452 0 1.11789447981141
A2BP1 0 0 4.53120676686483 1.34522603534256 0 1.74010724619747
A2LD1 6.94770472476424 7.92705080275384 6.40832124805635 6.5525507570889 7.2921559549592 7.46591652705797
A2ML1 0 0.41565051441473 0 0.597983993789946 0 0
A2M 12.413916703553 11.9979504885468 12.8200019062179 12.9645888051835 12.2914311784018 13.3435017632051
A4GALT 11.192440344074 9.91529337032864 11.792050825269 11.0094140803487 10.8173916627083 11.2086677724798
A4GNT 3.1585955515009 5.14529839229733 2.35741124701605 7.40469964993127 0.514097004894233 1.74010724619747
AAA1 0 0 0 0 0 0