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Remap values in pandas column with a dict
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It looks like this doesn't work anymore at all, which isn't surprising given the answer was from 4 years ago. This question needs a new answer given how general the operation is...
– PrestonH
Nov 21 '17 at 17:01
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How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
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JOIN two SELECT statement results
...COUNT(*) AS '# Late' FROM Table WHERE Age > Palt GROUP BY ks
Or UNION ALL if you want duplicates:
SELECT ks, COUNT(*) AS '# Tasks' FROM Table GROUP BY ks
UNION ALL
SELECT ks, COUNT(*) AS '# Late' FROM Table WHERE Age > Palt GROUP BY ks
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What is the right way to check for a null string in Objective-C?
...that people who are new to Objective C have trouble getting used to, especially coming form other languages where messages/method calls to nil crash.
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Do python projects need a MANIFEST.in, and what should be in it?
...oth, distutils and setuptools are including in source
distribution package all the files mentioned in setup.py - modules, package python files,
README.txt and test/test*.py. If this is all you want to have in distribution package, you do
not have to use MANIFEST.in.
If you want to manipulate (add o...
How to check if multiple array keys exists
... check (like in the original question), it's probably easy enough to just call array_key_exists() twice to check if the keys exists.
if (array_key_exists("story", $arr) && array_key_exists("message", $arr)) {
// Both keys exist.
}
However this obviously doesn't scale up well to many k...
Fastest way to check if a file exist using standard C++/C++11/C?
...e thousands of files and before doing something on them I need to check if all of them exist. What can I write instead of /* SOMETHING */ in the following function?
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Search and replace in bash using regular expressions
...'s are processed in order. Also, the g flag for the expression will match all occurrences in the input.
You can also pick your favorite tool using this method, i.e. perl, awk, e.g.:
echo "$MYVAR" | perl -pe 's/[a-zA-Z]/X/g and s/[0-9]/N/g'
This may allow you to do more creative matches... For ...
Truncate all tables in a MySQL database in one command?
Is there a query (command) to truncate all the tables in a database in one operation? I want to know if I can do this with one single query.
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Difference between Observer, Pub/Sub, and Data Binding
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Here's my take on the three:
Data Binding
Essentially, at the core this just means "the value of property X on object Y is semantically bound to the value of property A on object B. No assumptions are made as to how Y knows or is fed changes on object B.
Observer, or Obser...