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+--- Thread: String Method 'find(...)'. (/thread-16393.html)
String Method 'find(...)'. - ClassicalSoul - Feb-26-2019
Hi, I have a question about the string method 'find(...)'.
Consider the string 'tomato potato gelato'. How would I frame an optional argument such that the indexing would only begin at 'gelato'? In general terms, what I am trying to learn here is how to read function descriptions, because I don't get how the optional arguments work on the basis of the following description.
find(...) | S.find(sub[, start[, end]]) -> int | | Return the lowest index in S where substring sub is found, | such that sub is contained within S[start:end]. Optional | arguments start and end are interpreted as in slice notation.Thanks
RE: String Method 'find(...)'. - buran - Feb-26-2019
Output:mississippi
^ ^
3 6>>> 'mississippi'.find('si')
3
>>> 'mississippi'.find('si', 5)
6
RE: String Method 'find(...)'. - ClassicalSoul - Feb-27-2019
Do you know why the following method call is returning this?
>>> 'si si si no yes si'.find('i', 6, 10)
7I want it to return in failure, i.e. -1
RE: String Method 'find(...)'. - buran - Feb-27-2019
for index, ch in enumerate('si si si no yes si'):
print(f'{index} --> {ch}')
print('si si si no yes si'.find('i', 8, 10))Output:0 --> s
1 --> i
2 -->
3 --> s
4 --> i
5 -->
6 --> s
7 --> i
8 -->
9 --> n
10 --> o
11 -->
12 --> y
13 --> e
14 --> s
15 -->
16 --> s
17 --> i
-1
>>>