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Selecting multiple columns in a pandas dataframe
... is in the
3rd & 4th columns. If you don't know their names when your script runs, you can do this
newdf = df[df.columns[2:4]] # Remember, Python is 0-offset! The "3rd" entry is at slot 2.
As EMS points out in his answer, df.ix slices columns a bit more concisely, but the .columns slicing in...
Remove empty array elements
... answer on this topic is absolutely INCORRECT.
Consider the following PHP script:
<?php
$arr = array('1', '', '2', '3', '0');
// Incorrect:
print_r(array_filter($arr));
// Correct:
print_r(array_filter($arr, 'strlen'));
Why is this? Because a string containing a single '0' character also eva...
What is the difference between Xamarin.Form's LayoutOptions, especially Fill and Expand?
...quest="300">
<Label BackgroundColor="{StaticResource TileAlerts}"
HorizontalOptions="FillAndExpand"
Style="{StaticResource LabelStyleReversedLrg}"
HorizontalTextAlignment="Center"
Text="Alerts" />
...
Which is faster in Python: x**.5 or math.sqrt(x)?
...
Here are the results of your script: zoltan@host:~$ python2.5 p.py Took 0.183226 seconds Took 0.155829 seconds zoltan@host:~$ python2.4 p.py Took 0.181142 seconds Took 0.153742 seconds zoltan@host:~$ python2.6 p.py Took 0.157436 seconds Took 0.093905...
Why is document.write considered a “bad practice”?
...ndeed it could be considered an advantage for certain things, e.g., adding script elements (actually about the only thing I'd use DW for, and even then I'd think twice).
– nnnnnn
Dec 25 '11 at 12:16
...
How do I use cascade delete with SQL Server?
...Keys, and see which ones have "Cascade delete" turned on, you can run this script:
SELECT
OBJECT_NAME(f.parent_object_id) AS 'Table name',
COL_NAME(fc.parent_object_id,fc.parent_column_id) AS 'Field name',
delete_referential_action_desc AS 'On Delete'
FROM sys.foreign_keys AS f,
sys....
How to use '-prune' option of 'find' in sh?
...test
d ./dir1
d ./dir1/test
f ./dir1/test/file
f ./dir1/test/test
d ./dir1/scripts
f ./dir1/scripts/myscript.pl
f ./dir1/scripts/myscript.sh
f ./dir1/scripts/myscript.py
d ./dir2
d ./dir2/test
f ./dir2/test/file
f ./dir2/test/myscript.pl
f ./dir2/test/myscript.sh
$ find . -name test
./test
./dir1/t...
How to get Maven project version to the bash command line
... didn't find a switch for maven. Otherwise I'll just add some command line scripting to parse the version number.
– mkko
Aug 24 '10 at 5:47
83
...
Removing duplicate values from a PowerShell array
...single occurrences of a Row across said Columns, or develop an alternative script solution. Instead these cmdlets have only returned Rows in an Array that occurred ONCE with singular occurrence and dumped everything that had a duplicate. Typically I have to Remove Duplicates manually from the fina...
What does $@ mean in a shell script?
What does a dollar sign followed by an at-sign ( @ ) mean in a shell script?
6 Answers
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