Python String | find method
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Python's str.find(~) method returns the index of the first occurrence of the specified substring in the source string.
Parameters
1. sub | string
The substring to search for in source string.
2. start | number | optional
The index of the source string from which to start the search (inclusive). Defaults to 0 (start of source string).
3. end | number | optional
The index of the source string at which to end the search (exclusive). Defaults to len(source string) + 1.
Return value
If substring is found, then the index of the first character of the substring in the source string is returned. If not found, then -1 is returned.
Examples
Basic usage
To obtain the starting index of the first occurrence of "bc":
w = "abcdbc"w.find("bc")
1
The first occurrence of "bc" in "abcdbc" occurs at index position 1 (after the 'a').
Substring not found
To obtain the starting index of the first occurrence of "gg":
x = "abcdbc"x.find("gg")
-1
As "gg" was not found in "abcdbc", -1 is returned.
Start parameter
To start searching from index 2 (inclusive):
y = "abcdbc"y.find("bc", 2)
4
As the search starts from index position 2 (first 'c'), the first occurrence of "bc" is at index position 4.
End parameter
To stop searching at index 3 (exclusive):
z = "abcdbc"z.find("cd", 3)
-1
As the search ends at and is exclusive of index position 3 ('d'), no occurrence of "cd" is found and -1 is returned.
