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how do I insert a column at a specific column index in pandas?
...t columns as list, massage this as you want, and reindex your dataframe:
>>> cols = df.columns.tolist()
>>> cols = [cols[-1]]+cols[:-1] # or whatever change you need
>>> df.reindex(columns=cols)
n l v
0 0 a 1
1 0 b 2
2 0 c 1
3 0 d 2
EDIT: this can be d...
Which version of C# am I using
...w Framework version anyway:
C:\Windows\Microsoft.NET\Framework\v4.0.30319>csc /?
Microsoft (R) Visual C# 2010 Compiler version 4.0.30319.1
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How to multiply duration by integer?
...ystem (lack of operator overloading in this case) - you have to cast the multiplication to Duration * Duration = Duration, instead of the original one which actually makes more sense: Duration * int = Duration.
– Timmmm
Jan 5 '16 at 14:49
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How do I turn off “Automatically Switch to Debug Perspective” mode in eclipse?
...
Preferences -> Run/Debug -> Perspectives -> Open the associated perspective when application suspends
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add a string prefix to each value in a string column using Pandas
...
df['col'] = 'str' + df['col'].astype(str)
Example:
>>> df = pd.DataFrame({'col':['a',0]})
>>> df
col
0 a
1 0
>>> df['col'] = 'str' + df['col'].astype(str)
>>> df
col
0 stra
1 str0
...
How to change Hash values?
...ruby 2.4.0 you can use native Hash#transform_values method:
hash = {"a" => "b", "c" => "d"}
new_hash = hash.transform_values(&:upcase)
# => {"a" => "B", "c" => "D"}
There is also destructive Hash#transform_values! version.
...
How to fix java.lang.UnsupportedClassVersionError: Unsupported major.minor version
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IN eclipse project=>Proerties=>java compiler; set "the compiler compliance level" to the version according to your jre or jdk. As for me, it's 1.6 for jre 1.6
– Sam
Sep 25 '13 at 14:58
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Is it possible to delete an object's property in PHP?
...
unset($a->new_property);
This works for array elements, variables, and object attributes.
Example:
$a = new stdClass();
$a->new_property = 'foo';
var_export($a); // -> stdClass::__set_state(array('new_property' => 'fo...
Remap values in pandas column with a dict
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You can use .replace. For example:
>>> df = pd.DataFrame({'col2': {0: 'a', 1: 2, 2: np.nan}, 'col1': {0: 'w', 1: 1, 2: 2}})
>>> di = {1: "A", 2: "B"}
>>> df
col1 col2
0 w a
1 1 2
2 2 NaN
>>> df.replace({"col...
How do I manage MongoDB connections in a Node.js web application?
...xpress();
app.use('/api/users', usersRestApi);
app.get('/', (req, res) => {
res.send('Hello World');
});
// Create a MongoDB connection pool and start the application
// after the database connection is ready
MongoClient.connect(config.database.url, { promiseLibrary: Promise }, (err, db) =&g...