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Check for null in foreach loop
..., consider changing the getter of Headers instead. null is the value of unknown so if possible instead of using null as "I know there are no elements" when null actually(/originally) should be interpreted as "I don't know if there are any elements" use an empty set to show that you know there are no...
How do you tell someone they're writing bad code? [closed]
... way of doing things they might just decide to stick with the method they know. A compromise would be good, saying how you would do it and then subtly adding why your method is faster/better/etc.
– Mike B
Aug 5 '09 at 19:55
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Unable to import a module that is definitely installed
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maybe 2? I just don't know why it would install in the wrong place for this one library, where most others are fine.
– roy
Jan 12 '13 at 17:59
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Does Java casting introduce overhead? Why?
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Now the article is almost 20 years old. And the answers are also many years old. This question needs a modern answer.
– Raslanove
May 7 '19 at 6:00
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How to get script of SQL Server data? [duplicate]
...h from a database as well as insert the data in those tables (as far as I know you have to export all of the data in the selected tables however).
To do this follow these steps:
Right-click on your database and select Tasks > Generate Scripts
In the Generate and Publish Scripts wizard, select ...
How can I measure the speed of code written in PHP? [closed]
...rturbating element" is averaged.
Something like this, so, if you want to know how long it take to serialize an array :
$before = microtime(true);
for ($i=0 ; $i<100000 ; $i++) {
serialize($list);
}
$after = microtime(true);
echo ($after-$before)/$i . " sec/serialize\n";
Not perfect, but...
How to create a shared library with cmake?
...ritten a library that I used to compile using a self-written Makefile, but now I want to switch to cmake. The tree looks like this (I removed all the irrelevant files):
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How does a Java HashMap handle different objects with the same hash code?
...ith the keys of all pairs in the bucket, by comparing them with equals().
Now you can see how this is very efficient for looking up key-value pairs in a map: by the hash code of the key the hashmap immediately knows in which bucket to look, so that it only has to test against what's in that bucket....
What are the differences between Chosen and Select2?
...e ExpressionEngine add-on MX Select Plus (it is how I got here as there is now a competing add-on using Select2).
– notacouch
Jun 10 '13 at 17:20
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Converting a Pandas GroupBy output from Series to DataFrame
...tland"] } )
g1 = df1.groupby( [ "Name", "City"] ).count().reset_index()
Now you have your new dataframe in g1:
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