separating fields

Shell Programming and Scripting
1

Hi,

i have a file as follows:
jonathan:bonus1,bonus2
gerald:bonus1
patrick:bonus1,bonus2

My desired output is
jonathan:bonus1
jonathan:bonus2
gerald:bonus1
patrick:bonus1
patrick:bonus2

my current code is

cat $F | awk -F"[:,]"

how should i continue the code? Can i do something like
if NF = 3, print $1 $2\n print $1 $3. is this legal in a awk statement?

or its inappropriate to use awk here?

2 
awk 'BEGIN{FS="[:,]"}{for(i=2;i<=NF;i++)print $1":"$i}' file
3

Hi futurelet,

i tried to do it using the if way, and i could only managed to do it using 3 lines. The execution time is definitely longer than your suggestion, since i have to open the file 3 times. Is there any way i can modify it into 1 line? I appreciate your 'for' loop, its elegant and achieves the purpose. But i am raw to UNIX script, hoping to learn more ways to do it.

awk 'BEGIN(FS="[:,]"} { if (NF == 3) print $1":"$2)' $F
awk 'BEGIN(FS="[:,]"} { if (NF == 3) print $1":"$3)' $F
awk 'BEGIN(FS="[:,]"} { if (NF == 2) print $1":"$2)' $F

Would appreciate if anyone can suggest?

i am looking at something like
awk 'BEGIN(FS="[:,]"} { if (NF == 3) print $1":"$2 \n print $1":"$3 \n else print $1":"$2 print)' $F
but i got a bunch of syntax errors.

awk: cmd. line:1: BEGIN{FS="[:,]"}{if (NF == 2)print $1":"$2\n}
awk: cmd. line:1: ^ backslash not last chine

4

oneliner:

bash> OIFS=$IFS; IFS=: ; while read name rest; do echo ${rest} | tr ',' '\n' | sed s/^/$name\:/g; done <your_data_filename; IFS=$OIFS

script1:

#!/usr/bin/bash
file=your_data_filename
for line in `cat $file`; do 
        name=`echo $line | cut -d':' -f1` 
        rest=`echo $line | cut -d':' -f2` 
        for i in `echo $rest | tr ',' ' '`; do
                echo ${name}:${i}
        done
done

script2:

#!/usr/bin/bash
file=your_data_filename
for line in `cat $file`; do
        name=`echo $line | cut -d':' -f1` 
        rest=`echo $line | cut -d':' -f2` 
        echo $rest | tr ',' '\n' | sed s/^/$name\:/g
done
5

fast one liner:
while IFS=":," read e b1 b2 ; do echo "${e}:${b1}" ; [[ -n $b2 ]] && echo "${e}:${b2}" ; done < data

6

Hi Stobo, futurelet and Perderabo,

thank you all the the suggestions.

One small question thought, as i mentioned earlier, i am relatively new to scripting, how can i improve, to the extend i can come up with the one liners?

Will doing more scripting help or are there any references i can refer to ?