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Pointers in Python?
... know Python doesn't have pointers, but is there a way to have this yield 2 instead
9 Answers
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Is there an R function for finding the index of an element in a vector?
...rks on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
For multiple matching, %in% is the way to...
Is there an easy way to create ordinals in C#?
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21 Answers
21
Active
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How do you express binary literals in Python?
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298
For reference—future Python possibilities:
Starting with Python 2.6 you can express binary l...
Request failed: unacceptable content-type: text/html using AFNetworking 2.0
I'm trying out the new version 2.0 of AFNetworking and I'm getting the error above. Any idea why this is happening? Here's my code:
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App Inventor 2 Encrypt.Security 安全性扩展：MD5哈希，SHA1和SHA256哈希...
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App Inventor 2 Encrypt.Security 安全性扩...
Appending an element to the end of a list in Scala
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List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a complexity of O(n). If you need this operation frequently, or for long lists, consider using another data type (e.g. a ListBuffer).
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Regex to validate password strength
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edited Mar 29 '16 at 10:14
Alan Moore
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Convert columns to string in Pandas
...n (and therefore your keys to strings):
In [11]: df = pd.DataFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save t...
Test if a variable is a list or tuple
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edited Oct 2 '12 at 0:55
answered Feb 2 '10 at 15:29
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