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Convert pandas dataframe to NumPy array
I am interested in knowing how to convert a pandas dataframe into a NumPy array.
15 Answers
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How to shift a column in Pandas DataFrame
I would like to shift a column in a Pandas DataFrame , but I haven't been able to find a method to do it from the documentation without rewriting the whole DF. Does anyone know how to do it?
DataFrame:
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AngularJS : automatically detect change in model
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In views with {{}} and/or ng-model, Angular is setting up $watch()es for you behind the scenes.
By default $watch compares by reference. If you set the third parameter to $watch to true, Angular will instead "shallow" watch the object for cha...
Why does Java switch on contiguous ints appear to run faster with added cases?
... (bytecode instruction tableswitch).
However, once the JIT starts its job and compiles the bytecode into assembly, the tableswitch instruction does not always result in an array of pointers: sometimes the switch table is transformed into what looks like a lookupswitch (similar to an if/else if stru...
Validating IPv4 addresses with regexp
...aptured either way if we didn't have a full-match in the first place.
Old and shorter version (less readable) (63 chars)
^(?:(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])(\.(?!$)|$)){4}$
Older (readable) version (70 chars)
^(?:(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])(\.(?!$)|$)){4}$
It ...
iTerm2 keyboard shortcut - split pane navigation
I have been a long time user of the standard Mac Terminal. Decided to experiment with iTerm2 after hearing good things about it from my colleagues.
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How can I send an email by Java application using GMail, Yahoo, or Hotmail?
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First download the JavaMail API and make sure the relevant jar files are in your classpath.
Here's a full working example using GMail.
import java.util.*;
import javax.mail.*;
import javax.mail.internet.*;
public class Main {
private static String U...
Is there a way to suppress JSHint warning for one given line?
I have a (single) case in my app were eval is used, and I would like to suppress JSHint warning only for this case.
3 Ans...
is of a type that is invalid for use as a key column in an index
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A unique constraint can't be over 8000 bytes per row and will only use the first 900 bytes even then so the safest maximum size for your keys would be:
create table [misc_info]
(
[id] INTEGER PRIMARY KEY IDENTITY NOT NULL,
[key] nvarchar(450) UNIQUE NOT NULL,
[v...
How to import classes defined in __init__.py
...py
|-- helper.py
`-- settings.py
2 directories, 6 files
The command:
$ python import_submodule.py
Output:
settings
helper
Helper in lib.settings
someobject
Helper in lib.foo.someobject
# ./import_submodule.py
import fnmatch, os
from lib.settings import Values
from lib import Helper
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