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Float vs Decimal in ActiveRecord
...ation defines floats in binary format. Basically, it stores sign, fraction and exponent to represent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal for...
What open source C++ static analysis tools are available? [closed]
...ry good open source static analysis tools such as FindBugs , Checkstyle and PMD . Those tools are easy to use, very helpful, runs on multiple operating systems and free .
...
The difference between try/catch/throw and try/catch(e)/throw e
...milar in that both will catch every exception thrown inside the try block (and, unless you are simply using this to log the exceptions, should be avoided). Now look at these:
try { ... }
catch ()
{
/* ... */
throw;
}
try { ... }
catch (Exception e)
{
/* ... */
throw;
}
try { ... }...
Immutable vs Mutable types
... changing what the variable refers to. A mutable type can change that way, and it can also change "in place".
Here is the difference.
x = something # immutable type
print x
func(x)
print x # prints the same thing
x = something # mutable type
print x
func(x)
print x # might print something differe...
What is the python “with” statement designed for?
...r the first time today. I've been using Python lightly for several months and didn't even know of its existence! Given its somewhat obscure status, I thought it would be worth asking:
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How to check whether an array is empty using PHP?
... Done. I also changed it for the fact that you don't have to use isset and stuff.
– Tyler Carter
Feb 7 '10 at 6:35
5
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move_uploaded_file gives “failed to open stream: Permission denied” error
...g this error when trying to configure the upload directory with Apache 2.2 and PHP 5.3 on CentOS.
13 Answers
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Why in C++ do we use DWORD rather than unsigned int? [duplicate]
...fined in <windows.h>.
The reason is that DWORD has a specific range and format Windows functions rely on, so if you require that specific range use that type. (Or as they say "When in Rome, do as the Romans do.") For you, that happens to correspond to unsigned int, but that might not always b...
Expansion of variables inside single quotes in a command in Bash
I want to run a command from a bash script which has single quotes and some other commands inside the single quotes and a variable.
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How to unit test an object with database queries
I've heard that unit testing is "totally awesome", "really cool" and "all manner of good things" but 70% or more of my files involve database access (some read and some write) and I'm not sure how to write a unit test for these files.
...