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Why is my program slow when looping over exactly 8192 elements?
...rom the program in question. The matrix img[][] has the size SIZE×SIZE, and is initialized at:
2 Answers
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How to create custom easing function with Core Animation?
...tion curves in Core Animation
But I think it can be made a little simpler and more readable by using blocks. So we can define a category on CAKeyframeAnimation that looks something like this:
CAKeyframeAnimation+Parametric.h:
// this should be a function that takes a time value between
// 0.0 a...
What's valid and what's not in a URI query?
I've been Googling this back and forth reading RFCs and SO questions trying to crack this, but I still don't got jack.
7 An...
How to convert a data frame column to numeric type?
... 3
4 d 4 4 d 4
5 e 5 5 e 5
and let us run:
> sapply(d, mode)
char fake_char fac char_fac num
"character" "character" "numeric" "numeric" "numeric"
> sapply(d, class)
char fake_char fac char...
Failed to install Python Cryptography package with PIP and setup.py
... pip install cryptography or by downloading the package from their site and running python setup.py , I get the following error:
...
RegEx for matching UK Postcodes
...
I'd recommend taking a look at the UK Government Data Standard for postcodes [link now dead; archive of XML, see Wikipedia for discussion]. There is a brief description about the data and the attached xml schema provides a regular expression. It may not be exactly what you want bu...
Java how to replace 2 or more spaces with single space in string and delete leading and trailing spa
...);
See also
String.trim()
Returns a copy of the string, with leading and trailing whitespace omitted.
regular-expressions.info/Repetition
No trim() regex
It's also possible to do this with just one replaceAll, but this is much less readable than the trim() solution. Nonetheless, it's pro...
How to handle many-to-many relationships in a RESTful API?
Imagine you have 2 entities, Player and Team , where players can be on multiple teams. In my data model, I have a table for each entity, and a join table to maintain the relationships. Hibernate is fine at handling this, but how might I expose this relationship in a RESTful API?
...
Does ruby have real multithreading?
...e confusing two very different things here: the
Ruby Programming Language and the specific threading model of one
specific implementation of the Ruby Programming Language. There
are currently around 11 different implementations of the Ruby
Programming Language, with very different and unique thr...
Declaring variables inside or outside of a loop
...that str absolutely ought to be declared within the while loop. No ifs, no ands, no buts.
The only case where this rule might be violated is if for some reason it is of vital importance that every clock cycle must be squeezed out of the code, in which case you might want to consider instantiating s...