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Cast a Double Variable to Decimal
... No because it will throw an OverflowException double vol_y = (double)Decimal.MaxValue + 10E+28D; Console.WriteLine("Convert.ToDecimal(vol_y) = " + Convert.ToDecimal(vol_y));
– ToXinE
Dec 1 '14 at 15:23
...
Is “double hashing” a password less secure than just hashing it once?
...lled "key strengthening" or "key stretching". See en.wikipedia.org/wiki/Key_stretching
– user41871
Dec 7 '08 at 22:40
17
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How can I count the occurrences of a list item?
...by a constant factor of approximately 2.
Here is the script I used:
from __future__ import print_function
import timeit
t1=timeit.Timer('Counter(l)', \
'import random;import string;from collections import Counter;n=1000;l=[random.choice(string.ascii_letters) for x in range(n)]'
...
What does %w(array) mean?
... #Same as :'some words'
%s[other words] #Same as :'other words'
%s_last example_ #Same as :'last example'
Since Ruby 2.0.0 you also have:
%i( a b c ) # => [ :a, :b, :c ]
%i[ a b c ] # => [ :a, :b, :c ]
%i_ a b c _ # => [ :a, :b, :c ]
# etc...
...
Package objects
...initions get imported when someone outside of that package imports foo.bar._.
This way you can prevent to require the API client to issue additional imports to use your library effectively - e.g. in scala-swing you need to write
import swing._
import Swing._
to have all the goodness like onEDT a...
How to enumerate an enum with String type?
... at your own risk.
Here is the code:
func iterateEnum<T: Hashable>(_: T.Type) -> GeneratorOf<T> {
var cast: (Int -> T)!
switch sizeof(T) {
case 0: return GeneratorOf(GeneratorOfOne(unsafeBitCast((), T.self)))
case 1: cast = { unsafeBitCast(UInt8(truncating...
Split column at delimiter in data frame [duplicate]
...b','b|c','x|y'))
library(splitstackshape)
cSplit(df, "FOO", "|")
# ID FOO_1 FOO_2
# 1 11 a b
# 2 12 b c
# 3 13 x y
This particular function also handles splitting multiple columns, even if each column has a different delimiter:
df <- data.frame(ID=11:13,
...
What is the native keyword in Java for?
...in.c
#include <jni.h>
#include "Main.h"
JNIEXPORT jint JNICALL Java_Main_square(
JNIEnv *env, jobject obj, jint i) {
return i * i;
}
Compile and run:
sudo apt-get install build-essential openjdk-7-jdk
export JAVA_HOME='/usr/lib/jvm/java-7-openjdk-amd64'
javac Main.java
javah -jni Ma...
How can I escape square brackets in a LIKE clause?
...derscore from a query, so I ended up with this:
WHERE b.[name] not like '\_%' escape '\' -- use \ as the escape character
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...
Parameterize an SQL IN clause
...fun, this time, we'll use $ as the escape character.
select ...
where '|p_%t!r|'
like '%|' + REPLACE(REPLACE(REPLACE( 'p_%t!r' ,'$','$$'),'%','$%'),'_','$_') + '|%' escape '$'
I prefer this approach to escaping because it works in Oracle and MySQL as well as SQL Server. (I usually use the \ b...