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PHP: merge two arrays while keeping keys instead of reindexing?
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You can simply 'add' the arrays:
>> $a = array(1, 2, 3);
array (
0 => 1,
1 => 2,
2 => 3,
)
>> $b = array("a" => 1, "b" => 2, "c" => 3)
array (
'a' => 1,
'b' => 2,
'c' => 3,
)
>> $a + $b
array (
0 => 1,
1 => 2,
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Difference between break and continue statement
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21 Answers
21
Active
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Iterate a list with indexes in Python
...ar I've seen the function (or method) that takes a list, like this [3, 7, 19] and makes it into iterable list of tuples, like so: [(0,3), (1,7), (2,19)] to use it instead of:
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How assignment works with Python list slice?
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116
You are confusing two distinct operation that use very similar syntax:
1) slicing:
b = a[0:2...
Pandas dataframe get first row of each group
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>>> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 seco...
What is the difference between Ruby 1.8 and Ruby 1.9
I'm not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
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Creating dataframe from a dictionary where entries have different lengths
Say I have a dictionary with 10 key-value pairs. Each entry holds a numpy array. However, the length of the array is not the same for all of them.
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What is the most efficient way to create a dictionary of two pandas Dataframe columns?
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196
In [9]: pd.Series(df.Letter.values,index=df.Position).to_dict()
Out[9]: {1: 'a', 2: 'b', 3: 'c...
Select multiple columns in data.table by their numeric indices
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185
For versions of data.table >= 1.9.8, the following all just work:
library(data.table)
dt &...