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How can I make pandas dataframe column headers all lowercase?
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180
You can do it like this:
data.columns = map(str.lower, data.columns)
or
data.columns = [x.lo...
Scala constructor overload?
...tructors in Scala must either call the primary constructor (as in landon9720's) answer, or another auxiliary constructor from the same class, as their first action. They cannot simply call the superclass's constructor explicitly or implicitly as they can in Java. This ensures that the primary constr...
How would I get a cron job to run every 30 minutes?
I'm looking to add a crontab entry to execute a script every 30 minutes, on the hour and 30 minutes past the hour or something close. I have the following, but it doesn't seem to run on 0.
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Linear Layout and weight in Android
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answered Apr 23 '10 at 17:08
JeremyFromEarthJeremyFromEarth
14.1k44 gold badges2929 silver badges4646 bronze badges
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Check whether number is even or odd
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204
You can use the modulus operator, but that can be slow. If it's an integer, you can do:
if ( (...
What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* F...
Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
... to the process in question using gdb, and run:
p dup2(open("/dev/null", 0), 1)
p dup2(open("/dev/null", 0), 2)
detach
quit
e.g.:
$ tail -f /var/log/lastlog &
[1] 5636
$ ls -l /proc/5636/fd
total 0
lrwx------ 1 myuser myuser 64 Feb 27 07:36 0 -> /dev/pts/0
lrwx------ 1 myuser myuser 6...
Hadoop “Unable to load native-hadoop library for your platform” warning
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230
I assume you're running Hadoop on 64bit CentOS. The reason you saw that warning is the native Ha...
What do the different readystates in XMLHttpRequest mean, and how can I use them?
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The full list of readyState values is:
State Description
0 The request is not initialized
1 The request has been set up
2 The request has been sent
3 The request is in process
4 The request is complete
(from https://www.w3schools.com/js/js_ajax_http_respo...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
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+100
I'll consider the problem of many<->one/many casemappings first and separately from handling different Normalization forms.
Fo...