Homework & Coursework Questions

Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!

1. The problem statement, all variables and given/known data:
Filter a file for lines that have exactly 5 numbers in a row.


2. Relevant commands, code, scripts, algorithms:
Use the grep command with any options and wild cards.


3. The attempts at a solution (include all code and scripts):

Code:

 grep "[0-9]\{5\}" filterdata 
grep [0-9][0-9][0-9][0-9][0-9] filterdata
grep "[0-9]\{5,\}" filterdata
grep "[0-9]\{5\}" * filterdata
grep "[0-9]{5}" filterdata
grep "[0-9]\{5\}" . filterdata

(filterdata being the file Iam trying to Filter)


4. Complete Name of School (University), City (State), Country, Name of Professor, and Course Number (Link to Course):
Owens Community College, Toledo, Ohio, Thomas McLeary, EET 208

Note: Without school/professor/course information, you will be banned if you post here! You must complete the entire template (not just parts of it).

Code:

$ cat file
123456
12345
12345a dfdf
121
12345 dfd
$ grep -w "[0-9]\{5\}" file
12345
12345 dfd

Check out the ^ and $ anchors in regular expressions. Also it says "numbers", not "digits" . -w may work but is not a portable grep option.

So if a line is like :

Code:

bla 12 34 890 56 78 bla bla

... it does have exactly 5 numbers in a row

Thanks for the aid. Tried the grep -w "[0-9]\{5\} file with no luck. the numbers are consecutive (12345) and I need to show the complete line that they are in.

The solution just depends on the way you understand the statement :

Code:

"Filter a file for lines that have exactly 5 numbers in a row"

1) do "numbers" stand for "digit" ?

2) what does "in a row" mean ? separated by a space ? other ?

3) does this means that the lines does have and only have 5 numbers in a row?

4) or may the line contain other non-numeric characters (may those "5 numbers in a row" be placed anywhere in the line) ?

this line has four 1234 numbers
this line has five 12345 numbers
this line has six 123456 numbers
this line has seven 1234567 numbers
this line has eight 12345678 numbers
part one of the lab is to just return the line with five numbers.