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Adding new column to existing DataFrame in Python pandas
... a b c d
6 -0.269221 -0.026476 0.997517 1.294385
8 0.917438 0.847941 0.034235 -0.448948
>>> df1['e'] = pd.Series(np.random.randn(sLength), index=df1.index)
>>> df1
a b c d e
6 -0.269221 -0.026476 0.997517 ...
How do I loop through a date range?
...very third day starting with the "start" date, you could just call AddDays(3) in the loop instead of AddDays(1).
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Safe String to BigDecimal conversion
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edited Mar 12 '18 at 23:13
Bax
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answered Sep ...
How to concatenate strings with padding in sqlite
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Converting a column within pandas dataframe from int to string
...hape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
A B
0 0 1
1 2 3
2 4 5
3 6 7
4 8 9
In [18]: df.dtypes
Out[18]:
A int64
B int64
dtype: object
Convert a series
In [19]: df['A'].apply(str)
Out[19]:
0 0
1 2
2 4
3 6
4 8
Name: A, dtype: object
In [20]: df['A...
What's the fastest way to merge/join data.frames in R?
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DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = data.frame(b = c(1, 2, 3, 3, 4), c = letters[1:5])
merge(DF1, DF2)
b a c
1 1 1 a
2 2 1 b
3 3 2 c
4 3 2 d
5 4 2 e
DF1$c = DF2$c[match(DF1$b, DF2$b)]
DF1$c
[1] a b c e
Levels: a b c d e
> DF1
a b c
1 1 1 a
2 1 2 b
3 2 3 c
4 2 4 e
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In which language are the Java compiler and JVM written?
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edited Aug 3 '09 at 12:26
answered Aug 3 '09 at 6:47
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creating list of objects in Javascript
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var list = [
{ date: '12/1/2011', reading: 3, id: 20055 },
{ date: '13/1/2011', reading: 5, id: 20053 },
{ date: '14/1/2011', reading: 6, id: 45652 }
];
and then access it:
alert(list[1].date);
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How to deep copy a list?
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E0_copy is not a deep copy. You don't make a deep copy using list() (Both list(...) and testLis...