Grep commands for numbers w/decimal points

ETC Homework & Coursework Questions
1

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:
    Is there a grep commands for numbers w/decimal points
    Display lines for students with GPA above 3.69 but less than 4.0

  2. Relevant commands, code, scripts, algorithms: use of grep

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

grep '\<[3.69-4.00]\>' smallFile
grep: Invalid range end
 grep '\<[3.69-4.00]{3}\>' smallFile
grep: Invalid range end
grep '\<[3\.69-4\.00]{3}\>' smallFile
grep: Invalid range end
grep '\<[3\.69-4\.00]\>' smallFile
grep: Invalid range end
 grep [3\.69-4\.00] smallFile
grep: Invalid range end
 grep [3\.69-4\.00]{3} smallFile
grep: Invalid range end
grep '\<{3\.69-4\.00}\>' smallFile
grep {3\.69-4\.00} smallFile
grep 3\.69-4\.00 smallFile
grep 3.69-4.00 smallFile
 grep {3.69-4.00} smallFile
grep [3.69-4.00] smallFile

I have tried a lot of combinations no luck yet

Waubonsee Community College
Sugar Grove Illinois
Professor: Tim Lippold
Linux/UNIX Operating System CIS180
Book being used is Harley Hahn's Guide to Unix and Linux

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).

2

Hints:

  • For a start

means patterns matching anything between 3.70 and 3.99( you got rid of the odd cases!) ...
Remember grep is not looking for numeric but patterns ( string ) and now in what is left you have in common "3."

  • How would to look for all words starting with any letter between c and l ?
    How would you do that with numeric char?

My 2 cents

Good luck

3

does not work. A character set [ ] is a range for only one character!
As said in your other thread, you must have a character set for each relevant character position.
A 3 then a dot then a character set for the range 7-9 . This does not match a 4.00 and is correct because it should be less than 4.0.
If there are always two decimal digits then you can add a further character set [0-9] that means "any digit".

4

To be continued here.