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When should I use Struct vs. OpenStruct?
...
180
With an OpenStruct, you can arbitrarily create attributes. A Struct, on the other hand, must ha...
Controlling maven final name of jar artifact
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303
You set the finalName property in the plugin configuration section:
<plugin>
<gro...
How to match a String against string literals in Rust?
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101
You can do something like this:
match &stringthing[..] {
"a" => println!("0"),
...
How can I count the number of matches for a regex?
... following. (Starting from Java 9, there is a nicer solution)
int count = 0;
while (matcher.find())
count++;
Btw, matcher.groupCount() is something completely different.
Complete example:
import java.util.regex.*;
class Test {
public static void main(String[] args) {
String hel...
Code Golf: Collatz Conjecture
Inspired by http://xkcd.com/710/ here is a code golf for it.
70 Answers
70
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How to add leading zeros?
...f digits to begin with, so let's try a harder example of making powers of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but ...
MySQL Update Inner Join tables query
I have no idea what the problem is. Using MySQL 5.0 I get a compile error when attempting to run the following MySQL update query:
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What does the caret operator (^) in Python do?
...y one) of the operands (evaluates to) true.
To demonstrate:
>>> 0^0
0
>>> 1^1
0
>>> 1^0
1
>>> 0^1
1
To explain one of your own examples:
>>> 8^3
11
Think about it this way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
10...
How to print a percentage value in python?
...supports a percentage floating point precision type:
>>> print "{0:.0%}".format(1./3)
33%
If you don't want integer division, you can import Python3's division from __future__:
>>> from __future__ import division
>>> 1 / 3
0.3333333333333333
# The above 33% example wo...
SQL statement to select all rows from previous day
...rom one table. The table holds one datetime column. I am using SQL Server 2005.
11 Answers
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