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typeof !== “undefined” vs. != null
...n the two. In many cases, == can be better, because it tests for both null and undefined.
– seanmonstar
Jun 19 '12 at 16:58
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How does Junit @Rule work?
...n a more generic way.
For instance, ExternalResource executes code before and after a test method, without having to use @Before and @After. Using an ExternalResource rather than @Before and @After gives opportunities for better code reuse; the same rule can be used from two different test classes....
How do I remove duplicate items from an array in Perl?
..., but if you were to add sorting in this function then it would trump $::a and $::b, wouldn't it?
– vol7ron
Feb 21 '12 at 16:45
5
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What is the difference between Java RMI and RPC?
What is the actual difference between Java RMI and RPC?
8 Answers
8
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How to store a dataframe using Pandas
... it back using:
df = pd.read_pickle(file_name)
Note: before 0.11.1 save and load were the only way to do this (they are now deprecated in favor of to_pickle and read_pickle respectively).
Another popular choice is to use HDF5 (pytables) which offers very fast access times for large datasets:
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How to make jQuery to not round value returned by .width()?
I've searched around and couldn't find this. I'm trying to get the width of a div, but if it has a decimal point it rounds the number.
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In HTML5, is the localStorage object isolated per page/domain?
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It's per domain and port (the same segregation rules as the same origin policy), to make it per-page you'd have to use a key based on the location, or some other approach.
You don't need a prefix, use one if you need it though. Also, yes,...
What is the equivalent of the C++ Pair in Java?
...bout the relationship between the two values (how do you know what "first" and "second" mean ?).
A better practice is to write a very simple class, like the one Mike proposed, for each application you would have made of the Pair class. Map.Entry is an example of a pair that carry its meaning in its...
What's the difference between a catalog and a schema in a relational database?
... other things--all of the various schemas (external, conceptual, internal) and all of the corresponding mappings (external/conceptual, conceptual/internal) are kept.
In other words, the catalog contains detailed information (sometimes called descriptor information or metadata) regarding the va...
What is the difference between '&' and ',' in Java generics?
...you can restrict the type argument (in this case is T ) to extend a class and/or more interfaces with the 'and' operator ( & ) like this:
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