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Specifying rails version to use when creating a new application
I have two versions of rails (2.1.0 and 2.2.2) installed in my computer.
7 Answers
7
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What is the difference between exit(0) and exit(1) in C?
Can anyone tell me? What is the difference between exit(0) and exit(1) in C language?
11 Answers
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How can I remove a flag in C?
...ation of the flag you want to unset. A Bitwise NOT inverts every bit (i.e. 0 => 1, 1 => 0).
flags = flags & ~MASK; or flags &= ~MASK;.
Long Answer
ENABLE_WALK = 0 // 00000000
ENABLE_RUN = 1 // 00000001
ENABLE_SHOOT = 2 // 00000010
ENABLE_SHOOTRUN = 3 // 00000011
value ...
How does the static modifier affect this code?
...nd initialized with default values.
So now the values are:
A obj=null
num1=0
num2=0
The second phase, execution, starts from top to bottom. In Java, the execution starts from the first static members.
Here your first static variable is static A obj = new A();, so first it will create the object of...
What are best practices for validating email addresses on iOS 2.0
... the cleanest way to validate an email address that a user enters on iOS 2.0?
13 Answers
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How do I truncate a .NET string?
...lue;
return value.Length <= maxLength ? value : value.Substring(0, maxLength);
}
}
Now we can write:
var someString = "...";
someString = someString.Truncate(2);
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Cleaning `Inf` values from an R dataframe
..., function(x) replace(x, is.infinite(x),NA))))
## user system elapsed
# 0.52 0.01 0.53
# is.na (@dwin)
system.time(is.na(dat) <- sapply(dat, is.infinite))
# user system elapsed
# 32.96 0.07 33.12
# modified is.na
system.time(is.na(dat) <- do.call(cbind,lapply(dat, is.infini...
HTML5 Email Validation
...
120
In HTML5 you can do like this:
<form>
<input type="email" placeholder="Enter your emai...
Performance of foreach, array_map with lambda and array_map with static function
...W, I just did the benchmark since poster didn't do it. Running on PHP 5.3.10 + XDebug.
UPDATE 2015-01-22 compare with mcfedr's answer below for additional results without XDebug and a more recent PHP version.
function lap($func) {
$t0 = microtime(1);
$numbers = range(0, 1000000);
$ret = $f...
How to check whether a pandas DataFrame is empty?
...
505
You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print(...