shell scripting do loop -

sorry im new unix, wondering there anyway can make following code loop. example file name change every time 1 50

my script is

cut -d ' ' -f5- cd1_abcd_w.txt > cd1_rightformat.txt ; sed 's! \([^ ]\+\)\( \|$\)!\1 !g' cd1_rightformat.txt ; sed -i 's/ //g' cd1_rightformat.txt;  cut -d ' ' -f1-4 cd1_abcd_w.txt > cd1_extrainfo.txt ; 

i make loop cd1_abcd_w.txt become cd2_abcd_w.txt , output cd2_rightformat.txt etc...all way 50. cd$i.

many thanks

in bash, can use brace expansion:

for num in {1..10};     echo ${num} done 

similar basic for = 1 10 loop, it's inclusive @ both ends, loop output numbers 1 through 10.

you replace echo command whatever need do, such as:

cut -d ' ' -f5- cd${num}_abcd_w.txt >cd${num}_rightformat.txt # , on 

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if need numbers less ten have leading zero, change expression in for loop {01..50} instead. doesn't appear case here it's handy know.

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also in not-needed-but-handy-to-know category, can specify increment if don't want use default of one:

pax> num in {1..50..9}; echo ${num}; done 1 10 19 28 37 46 

(equivalent basic for = 1 50 step 9).