How can I use the UNIX shell to count the number of times a letter appears in a text file?

Question

I have a few text files and I\'d like to count how many times a letter appears in each?

Specifically, I\'d like to use the UNIX shell to do this, in the form of: cat fil

Answer 1

Alternative to grep:

sed 's/[^x]//g' filename | tr -d '\012' | wc -c

where x is the character you want to count.

Answer 2

Here is another way

cat  input_file | \
awk 'BEGIN {FS="x"; var=0 } \
{if (NF>0){ var=var + (NF-1) } } \
END{print var}'

where X is the character or string of characters you want to count and infile is the input file

Answer 3

awk '{ printf "%s\n", gsub( "ur_char", "oth_char", $0 ) }' < your_file_name > output.txt

you can add count of current line number to get the line numbers in awk also.

Answer 4

There's also awk:

$ echo -e "hello world\nbye all" | awk -Fl '{c += NF - 1} END {print c}'
5

Change -Fl to -F<your character>.

This works by setting the field delimiter to the character specified by -F, then accumulating the number of fields on each line - 1 (because if there's one delimiter, there are two fields - but we should only count 1).