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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?
...
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
...
creating list of objects in Javascript
...
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);
...
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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How to deep copy a list?
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239
E0_copy is not a deep copy. You don't make a deep copy using list() (Both list(...) and testLis...
Any implementation of Ordered Set in Java?
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answered Jan 3 '12 at 13:08
Chandra SekharChandra Sekhar
14.8k1010 gold badges6666 silver badges8686 bronze badges
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What's the best way to generate a UML diagram from Python source code? [closed]
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136
You may have heard of Pylint that helps statically checking Python code. Few people know that i...
List comprehension rebinds names even after scope of comprehension. Is this right?
...omprehensions leak the loop control variable in Python 2 but not in Python 3. Here's Guido van Rossum (creator of Python) explaining the history behind this:
We also made another change in Python
3, to improve equivalence between list
comprehensions and generator
expressions. In Python 2,...
Return multiple columns from pandas apply()
...ue) + ' MB'
s['size_gb'] = locale.format("%.1f", s['size'] / 1024.0 ** 3, grouping=True) + ' GB'
return s
df_test = df_test.append(rows_list)
df_test = df_test.apply(sizes, axis=1)
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