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Getting and removing the first character of a string
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answered Mar 14 '14 at 9:41
bartektartanusbartektartanus
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Create a variable name with “paste” in R?
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4 Answers
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Active
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Append column to pandas dataframe
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45
Or pd.concat([dat1, dat2], axis=1) in this case.
– DSM
Dec 16 '13 at 3:35
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mongodb group values by multiple fields
... {
"book" : "book4",
"count" : 1
},
{
"book" : "book5",
"count" : 1
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std::next_permutation Implementation Explanation
...td:next_permutation was implemented so I extracted the the gnu libstdc++ 4.7 version and sanitized the identifiers and formatting to produce the following demo...
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Is there a JavaScript strcmp()?
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leaf
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answered Jul 24 '09 at 18:38
newacctnewacct
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How can I remove a flag in C?
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342
Short Answer
You want to do an Bitwise AND operation on the current value with a Bitwise NOT o...
What is the easiest way to push an element to the beginning of the array?
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answered May 22 '11 at 1:48
mu is too shortmu is too short
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Efficient way to apply multiple filters to pandas DataFrame or Series
...ite helper functions for this, consider something along these lines:
In [14]: def b(x, col, op, n):
return op(x[col],n)
In [15]: def f(x, *b):
return x[(np.logical_and(*b))]
In [16]: b1 = b(df, 'col1', ge, 1)
In [17]: b2 = b(df, 'col1', le, 1)
In [18]: f(df, b1, b2)
O...
Convert columns to string in Pandas
...refore 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 this to, al...