Combine columns from multiple files using awk - awk

Question

I have a set of files in a folder like this:
hsa-miR-106a-5p.filtered.txt hsa-miR-182-5p.filtered.txt hsa-miR-2467-5p.filtered.txt hsa-miR-421.filtered.txt hsa-miR-592.filtered.txt
hsa-miR-106b-3p.filtered.txt hsa-miR-183-3p.filtered.txt hsa-miR-25-3p.filtered.txt hsa-miR-424-3p.filtered.txt hsa-miR-615-3p.filtered.txt
hsa-miR-106b-5p.filtered.txt hsa-miR-183-5p.filtered.txt hsa-miR-25-5p.filtered.txt hsa-miR-424-5p.filtered.txt hsa-miR-625-3p.filtered.txt
hsa-miR-1180-3p.filtered.txt hsa-miR-188-5p.filtered.txt hsa-miR-27a-3p.filtered.txt hsa-miR-431-5p.filtered.txt hsa-miR-625-5p.filtered.txt
hsa-miR-1246.filtered.txt hsa-miR-18a-3p.filtered.txt hsa-miR-27a-5p.filtered.txt
file:
ENSG00000224531.4 SMIM13 ENST00000416247.2 9606 hsa-miR-135b-5p 3 132 139 -0.701 99 -0.701 99
ENSG00000112357.8 PEX7 ENST00000541292.1 9606 hsa-miR-135b-5p 3 428 435 -0.683 99 -0.640 99
ENSG00000138279.11 ANXA7 ENST00000372921.5 9606 hsa-miR-135b-5p 3 205 212 -0.631 99 -0.631 99
ENSG00000135248.11 FAM71F1 ENST00000315184.5 9606 hsa-miR-135b-5p 3 488 495 -0.581 99 -0.581 99
ENSG00000087302.4 C14orf166 ENST00000556760.1 9606 hsa-miR-135b-5p 3 34 41 -0.566 99 -0.566 99
ENSG00000104722.9 NEFM ENST00000433454.2 9606 hsa-miR-135b-5p 3 25 32 -0.565 99 -0.565 99
ENSG00000132485.8 ZRANB2 ENST00000254821.6 9606 hsa-miR-135b-5p 3 284 291 -0.566 99 -0.565 99
ENSG00000185127.5 C6orf120 ENST00000332290.2 9606 hsa-miR-135b-5p 3 125 132 -0.564 99 -0.553 99
I would like to combine the rows for all files so that I get one output files that contain all the rows.
I have been playing around with R, but decided I wanted to try awk:
for f in *.filtered.txt
do
....
done

Answer 1

Maybe this can help you (R solution):
files <- dir(pattern="\\.txt$") # Get the field list and put it in a vector
df <- NA # Initialize the variable that will hold the data frame
for(f in files){
if(is.na(df)) { # If the dataframe is empty ...
df <- read.table(f) # ... read the first file in the list
} else { # ... otherwise ...
df <- rbind(df, read.table(f)) # ... bind the dataframe with the rows
# from the next file
}
}