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Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
How to open, read, and write from serial port in C?
...en), and just copy and paste the bits needed into each project.
You must call cfmakeraw on a tty obtained from tcgetattr. You cannot zero-out a struct termios, configure it, and then set the tty with tcsetattr. If you use the zero-out method, then you will experience unexplained intermittent failur...
subtle differences between JavaScript and Lua [closed]
...= operators are of lower precedence than >, >=, <, <=. In Lua, all comparison operators are the same precedence.
Lua supports tail calls.
UPDATE: JS now supports tail calls.
Lua supports assignment to a list of variables. While it isn't yet standard in Javascript, Mozilla's JS engine ...
How can I use pointers in Java?
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All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
Is there a performance difference between i++ and ++i in C++?
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However, if i is an instance of a C++ class, then i++ and ++i are making calls to one of the operator++ functions. Here's a standard pair of these functions:
Foo& Foo::operator++() // called for ++i
{
this->data += 1;
return *this;
}
Foo Foo::operator++(int ignored_dummy_value) ...
How can I fix the Microsoft Visual Studio error: “package did not load correctly”?
I installed Visual Studio 2012 and DevExpress 13.1. As Visual Studio started, it generated an error shown by this attached image,
...
Batch file to delete files older than N days
I am looking for a way to delete all files older than 7 days in a batch file. I've searched around the web, and found some examples with hundreds of lines of code, and others that required installing extra command line utilities to accomplish the task.
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
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I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
throw Error('msg') vs throw new Error('msg')
...this is explicitly stated in the specification:
... Thus the function call Error(…) is equivalent to the object creation expression new Error(…) with the same arguments.
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How can I print the contents of a hash in Perl?
I keep printing my hash as # of buckets / # allocated.
How do I print the contents of my hash?
11 Answers
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