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What happens to a declared, uninitialized variable in C? Does it have a value?
...ile scope and function static) are initialized to zero:
int x; // zero
int y = 0; // also zero
void foo() {
static int x; // also zero
}
Non-static variables (local variables) are indeterminate. Reading them prior to assigning a value results in undefined behavior.
void foo() {
int x;
...
Curly braces in string in PHP
What is the meaning of { } (curly braces) in string literals in PHP?
5 Answers
5
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Adding new column to existing DataFrame in Python pandas
...h), index=df1.index)
Edit 2015
Some reported getting the SettingWithCopyWarning with this code.
However, the code still runs perfectly with the current pandas version 0.16.1.
>>> sLength = len(df1['a'])
>>> df1
a b c d
6 -0.269221 -0.026476 0...
Entity Framework: One Database, Multiple DbContexts. Is this a bad idea? [closed]
My impression to date has been that a DbContext is meant to represent your database, and thus, if your application uses one database, you'd want only one DbContext .
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Use 'import module' or 'from module import'?
...st to use import module or from module import . I've just started with Python and I'm trying to start off with best practices in mind.
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Is it possible to rotate a drawable in the xml description?
...reating an app, with resources that can be reused (because buttons are always the same, but mirrored or rotated). I do want to use the same resource so I don't have to add 3 more resources that are exactly like the original but rotated. But I also don't want to mix the code with things that can be d...
What does it mean to “program to an interface”?
...this mentioned a few times and I am not clear on what it means. When and why would you do this?
32 Answers
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Resolve build errors due to circular dependency amongst classes
I often find myself in a situation where I am facing multiple compilation/linker errors in a C++ project due to some bad design decisions (made by someone else :) ) which lead to circular dependencies between C++ classes in different header files (can happen also in the same file) . But fortunately...
what does -webkit-transform: translate3d(0,0,0); exactly do? Apply to body?
what does -webkit-transform: translate3d(0,0,0); exactly do?
Does it have any performance issues? Should I just apply it to the body or individual elements? It seems to improve scroll events drastically.
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Set environment variables on Mac OS X Lion
When someone says "edit your .plist file" or "your .profile" or ".bash_profile" etc, this just confuses me. I have no idea where these files are, how to create them if I have to do that, etc, and also why there seem to be so many different ones (why? Do they do different things?)
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