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how do you filter pandas dataframes by multiple columns
To filter a dataframe (df) by a single column, if we consider data with male and females we might:
6 Answers
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force browsers to get latest js and css files in asp.net application
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I solved this by tacking a last modified timestamp as a query parameter to the scripts.
I did this with an extension method, and using it in my CSHTML files. Note: this implementation caches the timestamp for 1 minute so we don't thrash the disk quite so much.
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Export and Import all MySQL databases at one time
...ve more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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How to convert a LocalDate to an Instant?
I work with the new DateTime API of Java 8.
2 Answers
2
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What are the GCC default include directories?
When I compile a very simple source file with gcc I don't have to specify the path to standard include files such as stdio or stdlib.
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How can I check whether Google Maps is fully loaded?
...ddListenerOnce(map, 'idle', function(){
// do something only the first time the map is loaded
});
The "idle" event is triggered when the map goes to idle state - everything loaded (or failed to load). I found it to be more reliable then tilesloaded/bounds_changed and using addListenerOnce meth...
:: (double colon) operator in Java 8
I was exploring the Java 8 source and found this particular part of code very surprising:
17 Answers
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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...ide a (presumed) loop, so that doesn't normally contribute any significant time. Along with reducing the number of branch instructions, this also (generally) improves branch prediction. In this case, the same branch is taken whether the number is below the bottom end or above the top end of the rang...
Condition within JOIN or WHERE
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I recommend you write the queries in the most readable way possible.
Sometimes this includes making the INNER JOIN relatively "incomplete" and putting some of the criteria in the WHERE simply to make the lists of filtering criteria more easily maintainable.
For example, instead of:
SELECT *
FROM...
Can you get DB username, pw, database name in Rails?
I'm writing a rake task that does some DB work outside of Rails/ActiveRecord.
5 Answers
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