What is the use of keyword 'force' & this code snippet is not showing 'bats'

Question

This code snippet is not showing 'bats' & moreover 'eats' is showing as 'eat' in the last? When I don't use '[force]' 7 'at' is showing? What is the use of 'force'?

t="A fat cat doesn't eat oat but a rat eats bats."
mo = re.findall("[force]at", t)
print(mo)
['fat', 'cat', 'eat', 'oat', 'rat', 'eat']

"It is the Jedi's ability to recognize the Force in himself and to use it to his benefit." — Yury Tarabanko, Jul 27 '19 at 12:57
`force` is not a keyword. `[abc]` means "either a or b or c", so `[force]` is "either f or o or r etc". You could use `[focer]` with the same result. As of the `s` you never told regex to match anything beyond "at" — Yury Tarabanko, Jul 27 '19 at 13:01
How can I represent the all the alphabets in this [] instead of writing specific characters — Matt Joy, Jul 27 '19 at 13:11
Got it. But if I use this [a-z]at[a-z] then I'm only getting 2 matches — Matt Joy, Jul 27 '19 at 13:18

score 1 · Accepted Answer · answered Jul 27 '19 at 13:12

One of places where you can find explanation of Python regular expressions is re module docs, in your case - [force]at relevant part is that [] is

Used to indicate a set of characters. In a set:
Characters can be listed individually, e.g. [amk] will match 'a', 'm', or 'k'.

Therefore [force]at will match: fat, oat, rat, cat, eat.

ncica · Answer 2 · 2019-07-27T12:55:46.510

0

you can use:

import re
t="A fat cat doesn't eat oat but a rat eats bats."
mo = re.findall("\w*at\w*", t)
print(mo)

output:

['fat', 'cat', 'eat', 'oat', 'rat', 'eats', 'bats']

\w* matches any word character (equal to [a-zA-Z0-9_])

* Quantifier — Matches between zero and unlimited times, as many times as possible, giving back as needed (greedy)

[force]at

Match a single character present in the list below [force] force matches a single character in the list force (case sensitive) at matches the characters at literally (case sensitive)

edited Jul 27 '19 at 12:55

answered Jul 27 '19 at 12:53

ncica

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Thanks. Just wanted to ask what is the use of force keyword – Matt Joy Jul 27 '19 at 12:55
check my edit :) – ncica Jul 27 '19 at 12:58
`force` is not a keyword here. It’s just the set of characters f, o, r, c and e. You could use `cefor` or any other permutation of those 5 characters and have the same effect. – Chris Johnson Jul 27 '19 at 13:10

score 0 · Answer 3 · answered Jul 27 '19 at 12:54

0

Play around with regex here. There you have an explanation for your whole regex you use. I.e. comare it to [fc]at to get a feeling for it.

answered Jul 27 '19 at 12:54

Manuel

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What is the use of keyword 'force' & this code snippet is not showing 'bats'

3 Answers3