Transpose a txt file

Hello,
I have a text file with 148 rows and 2532691 columns. I need to transpose the data. The command that I am using is

 awk '
{ 
    for (i=1; i<=NF; i++)  {
        a[NR,i] = $i
    }
}
NF>p { p = NF }
END {    
    for(j=1; j<=p; j++) {
        str=a[1,j]
        for(i=2; i<=NR; i++){
            str=str" "a[i,j];
        }
        print str
    }
}' file.raw > output

does not work for me due to memory issues -> the job crashes over the server. Is there a better way to handle the data?
many thanks

I dont know awk well enough, but i wouldnt think that it causes a memory issue.
This said, to me it seems that these parts might be the cause:

str=a[1,j]
    str=str" "a[i,j];

Other than that, i dont see a to be initalized at all.

hth

Using intermediate files will relieve memory. Try

awk '{$1=$1; print > "FILE"NR}' FS="," OFS="\n" file.raw
paste FILE* > output

Thank you, But still running into memory issues. This is my script

awk '{$1=$1; print > "FILE"NR}' FS="," OFS="\n" file.raw

 awk '
{ 
    for (i=1; i<=NF; i++)  {
        a[NR,i] = $i
    }
}
NF>p { p = NF }
END {    
    for(j=1; j<=p; j++) {
        str=a[1,j]
        for(i=2; i<=NR; i++){
            str=str" "a[i,j];
        }
        print str
    }
}' FILE* | paste FILE* > output

I'm absolutely not sure why you tear apart my two commands and then complain it wouldn't work.
To prove it works, try smaller but representative sample files.

well, because

awk '{$1=$1; print > "FILE"NR}' FS="," OFS="\n" file.raw

is only splitting the file into rows and not transposing it to columns. So my intenstion was to split the rows and transpose it and then join all the columns..

What's your field separator? If space, drop the FS="," . If other, use that for the FS variable.