Function to return subword of a camelcase string
up vote
6
down vote
favorite
Given a camelcase string and an index, return the subword of the string that includes that index, e.g.:
find_word('CamelCaseString', 6) -> 'Case'
find_word('ACamelCaseString', 0) -> 'A'
My code:
def find_word(s, index):
for i in range(index, 0, -1):
if s[i].isupper():
left = i
break
else:
left = 0
for i in range(index, len(s)-1):
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
right = i
break
else:
right = len(s) - 1
return s[left:right+1]
Can this be made more concise/efficient?
python strings interview-questions
add a comment |
up vote
6
down vote
favorite
Given a camelcase string and an index, return the subword of the string that includes that index, e.g.:
find_word('CamelCaseString', 6) -> 'Case'
find_word('ACamelCaseString', 0) -> 'A'
My code:
def find_word(s, index):
for i in range(index, 0, -1):
if s[i].isupper():
left = i
break
else:
left = 0
for i in range(index, len(s)-1):
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
right = i
break
else:
right = len(s) - 1
return s[left:right+1]
Can this be made more concise/efficient?
python strings interview-questions
Shouldn't the first example returnString
?
– Heslacher
7 hours ago
1
No, the index 6 is character'a'
in subword'Case'
.
– Eugene Yarmash
7 hours ago
OK, now I got it.
– Heslacher
7 hours ago
add a comment |
up vote
6
down vote
favorite
up vote
6
down vote
favorite
Given a camelcase string and an index, return the subword of the string that includes that index, e.g.:
find_word('CamelCaseString', 6) -> 'Case'
find_word('ACamelCaseString', 0) -> 'A'
My code:
def find_word(s, index):
for i in range(index, 0, -1):
if s[i].isupper():
left = i
break
else:
left = 0
for i in range(index, len(s)-1):
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
right = i
break
else:
right = len(s) - 1
return s[left:right+1]
Can this be made more concise/efficient?
python strings interview-questions
Given a camelcase string and an index, return the subword of the string that includes that index, e.g.:
find_word('CamelCaseString', 6) -> 'Case'
find_word('ACamelCaseString', 0) -> 'A'
My code:
def find_word(s, index):
for i in range(index, 0, -1):
if s[i].isupper():
left = i
break
else:
left = 0
for i in range(index, len(s)-1):
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
right = i
break
else:
right = len(s) - 1
return s[left:right+1]
Can this be made more concise/efficient?
python strings interview-questions
python strings interview-questions
asked 7 hours ago
Eugene Yarmash
26329
26329
Shouldn't the first example returnString
?
– Heslacher
7 hours ago
1
No, the index 6 is character'a'
in subword'Case'
.
– Eugene Yarmash
7 hours ago
OK, now I got it.
– Heslacher
7 hours ago
add a comment |
Shouldn't the first example returnString
?
– Heslacher
7 hours ago
1
No, the index 6 is character'a'
in subword'Case'
.
– Eugene Yarmash
7 hours ago
OK, now I got it.
– Heslacher
7 hours ago
Shouldn't the first example return
String
?– Heslacher
7 hours ago
Shouldn't the first example return
String
?– Heslacher
7 hours ago
1
1
No, the index 6 is character
'a'
in subword 'Case'
.– Eugene Yarmash
7 hours ago
No, the index 6 is character
'a'
in subword 'Case'
.– Eugene Yarmash
7 hours ago
OK, now I got it.
– Heslacher
7 hours ago
OK, now I got it.
– Heslacher
7 hours ago
add a comment |
1 Answer
1
active
oldest
votes
up vote
7
down vote
Review
Add docstrings and tests... or both in the form of doctests!
def find_word(s, index):
"""
Finds the CamalCased word surrounding the givin index in the string
>>> find_word('CamelCaseString', 6)
'Case'
>>> find_word('ACamelCaseString', 0)
'A'
"""
...
Loop like a native.
Instead of going over the indexes we can loop over the item directly
range(index, 0, -1)
We can loop over the item and index at the same time using enumerate
for i, s in enumerate(string[index:0:-1])
However this would be slower since it will create a new string object with every slice.
If we can be sure that the givin string is a CamalCase string
Then we can drop some of your second if statement
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
Would be
if s[i+1].isupper():
Actually your code (from a performance aspect) is quite good
We could however use a while loop to increment both side at once, for a little performance gain.
(slower, yet more readable) Alternative
A different approach to finding CamalCase words can be done with regex,
We can find all CamalCase words with the following regex: r"([A-Z][a-z]*)"
And we can use re.finditer
to create a generator for our matches and loop over them, and return when our index is in between the end and the start.
import re
def find_word_2(string, index):
for match in re.finditer(r"([A-Z][a-z]*)", string):
if match.start() <= index < match.end():
return match.group()
NOTE This yields more readable code, but it should be alot slower for large inputs.
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
7
down vote
Review
Add docstrings and tests... or both in the form of doctests!
def find_word(s, index):
"""
Finds the CamalCased word surrounding the givin index in the string
>>> find_word('CamelCaseString', 6)
'Case'
>>> find_word('ACamelCaseString', 0)
'A'
"""
...
Loop like a native.
Instead of going over the indexes we can loop over the item directly
range(index, 0, -1)
We can loop over the item and index at the same time using enumerate
for i, s in enumerate(string[index:0:-1])
However this would be slower since it will create a new string object with every slice.
If we can be sure that the givin string is a CamalCase string
Then we can drop some of your second if statement
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
Would be
if s[i+1].isupper():
Actually your code (from a performance aspect) is quite good
We could however use a while loop to increment both side at once, for a little performance gain.
(slower, yet more readable) Alternative
A different approach to finding CamalCase words can be done with regex,
We can find all CamalCase words with the following regex: r"([A-Z][a-z]*)"
And we can use re.finditer
to create a generator for our matches and loop over them, and return when our index is in between the end and the start.
import re
def find_word_2(string, index):
for match in re.finditer(r"([A-Z][a-z]*)", string):
if match.start() <= index < match.end():
return match.group()
NOTE This yields more readable code, but it should be alot slower for large inputs.
add a comment |
up vote
7
down vote
Review
Add docstrings and tests... or both in the form of doctests!
def find_word(s, index):
"""
Finds the CamalCased word surrounding the givin index in the string
>>> find_word('CamelCaseString', 6)
'Case'
>>> find_word('ACamelCaseString', 0)
'A'
"""
...
Loop like a native.
Instead of going over the indexes we can loop over the item directly
range(index, 0, -1)
We can loop over the item and index at the same time using enumerate
for i, s in enumerate(string[index:0:-1])
However this would be slower since it will create a new string object with every slice.
If we can be sure that the givin string is a CamalCase string
Then we can drop some of your second if statement
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
Would be
if s[i+1].isupper():
Actually your code (from a performance aspect) is quite good
We could however use a while loop to increment both side at once, for a little performance gain.
(slower, yet more readable) Alternative
A different approach to finding CamalCase words can be done with regex,
We can find all CamalCase words with the following regex: r"([A-Z][a-z]*)"
And we can use re.finditer
to create a generator for our matches and loop over them, and return when our index is in between the end and the start.
import re
def find_word_2(string, index):
for match in re.finditer(r"([A-Z][a-z]*)", string):
if match.start() <= index < match.end():
return match.group()
NOTE This yields more readable code, but it should be alot slower for large inputs.
add a comment |
up vote
7
down vote
up vote
7
down vote
Review
Add docstrings and tests... or both in the form of doctests!
def find_word(s, index):
"""
Finds the CamalCased word surrounding the givin index in the string
>>> find_word('CamelCaseString', 6)
'Case'
>>> find_word('ACamelCaseString', 0)
'A'
"""
...
Loop like a native.
Instead of going over the indexes we can loop over the item directly
range(index, 0, -1)
We can loop over the item and index at the same time using enumerate
for i, s in enumerate(string[index:0:-1])
However this would be slower since it will create a new string object with every slice.
If we can be sure that the givin string is a CamalCase string
Then we can drop some of your second if statement
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
Would be
if s[i+1].isupper():
Actually your code (from a performance aspect) is quite good
We could however use a while loop to increment both side at once, for a little performance gain.
(slower, yet more readable) Alternative
A different approach to finding CamalCase words can be done with regex,
We can find all CamalCase words with the following regex: r"([A-Z][a-z]*)"
And we can use re.finditer
to create a generator for our matches and loop over them, and return when our index is in between the end and the start.
import re
def find_word_2(string, index):
for match in re.finditer(r"([A-Z][a-z]*)", string):
if match.start() <= index < match.end():
return match.group()
NOTE This yields more readable code, but it should be alot slower for large inputs.
Review
Add docstrings and tests... or both in the form of doctests!
def find_word(s, index):
"""
Finds the CamalCased word surrounding the givin index in the string
>>> find_word('CamelCaseString', 6)
'Case'
>>> find_word('ACamelCaseString', 0)
'A'
"""
...
Loop like a native.
Instead of going over the indexes we can loop over the item directly
range(index, 0, -1)
We can loop over the item and index at the same time using enumerate
for i, s in enumerate(string[index:0:-1])
However this would be slower since it will create a new string object with every slice.
If we can be sure that the givin string is a CamalCase string
Then we can drop some of your second if statement
if s[i].islower() and s[i+1].isupper() or s[i:i+2].isupper():
Would be
if s[i+1].isupper():
Actually your code (from a performance aspect) is quite good
We could however use a while loop to increment both side at once, for a little performance gain.
(slower, yet more readable) Alternative
A different approach to finding CamalCase words can be done with regex,
We can find all CamalCase words with the following regex: r"([A-Z][a-z]*)"
And we can use re.finditer
to create a generator for our matches and loop over them, and return when our index is in between the end and the start.
import re
def find_word_2(string, index):
for match in re.finditer(r"([A-Z][a-z]*)", string):
if match.start() <= index < match.end():
return match.group()
NOTE This yields more readable code, but it should be alot slower for large inputs.
answered 6 hours ago
Ludisposed
6,93921959
6,93921959
add a comment |
add a comment |
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Shouldn't the first example return
String
?– Heslacher
7 hours ago
1
No, the index 6 is character
'a'
in subword'Case'
.– Eugene Yarmash
7 hours ago
OK, now I got it.
– Heslacher
7 hours ago