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Pass a data.frame column name to a function
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109
You can just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 &...
What is the fastest method for selecting descendant elements in jQuery?
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Method 1 and method 2 are identical with the only difference is that method 1 needs to parse the scope passed and translate it to a call to $parent.find(".child").show();.
Method 4 and Method 5 both need to parse the selector and ...
Numbering rows within groups in a data frame
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edited Mar 14 '17 at 22:06
Frank
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Numpy: Divide each row by a vector element
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187
Here you go. You just need to use None (or alternatively np.newaxis) combined with broadcastin...
Pandas get topmost n records within each group
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195
Did you try df.groupby('id').head(2)
Ouput generated:
>>> df.groupby('id').head(2)...
php中json_decode()和json_encode()的使用方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
php中json_decode()和json_encode()的使用方法1.json_decode()json_decode(PHP 5 >= 5.2.0, PECL json >= 1.2.0)json_decode — 对 JSON 格式的字符串进行编码说明mixed jso...1.json_decode()
(PHP 5 >= 5.2.0, PECL json >= 1.2.0)
对 JSON 格式的字符串进行编码
说明：
mix...
Convert a row of a data frame to vector
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156
When you extract a single row from a data frame you get a one-row data frame. Convert it to a...
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 does this square bracket and parenthesis bracket notation mean [first1,last1)?
I have seen number ranges represented as [first1,last1) and [first2,last2) .
4 Answers
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How do I find the duplicates in a list and create another list with them?
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