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What does glLoadIdentity() do in OpenGL?
...lent of 1, is not exactly correct. The matrix actually looks like this:
1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
That is the identity matrix. Boon is correct, mathematically, that any matrix multiplied with that matrix (or a matrix that looks like that; diagonal ones, all else 0s) will result in the origi...
How to calculate the difference between two dates using PHP?
...rom this it's rather easy to calculate different time periods.
$date1 = "2007-03-24";
$date2 = "2009-06-26";
$diff = abs(strtotime($date2) - strtotime($date1));
$years = floor($diff / (365*60*60*24));
$months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
$days = floor(($diff - $years ...
Detecting a mobile browser
...opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|series(4|6)0|symbian|treo|up\.(browser|link)|vodafone|wap|windows ce|xda|xiino/i.test(a)||/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|...
PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
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170
After the first foreach loop, $item is still a reference to some value which is also being used ...
Why does Lua have no “continue” statement?
...Lua 5.2 the best workaround is to use goto:
-- prints odd numbers in [|1,10|]
for i=1,10 do
if i % 2 == 0 then goto continue end
print(i)
::continue::
end
This is supported in LuaJIT since version 2.0.1
share
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Alternatives to gprof [closed]
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answered Dec 19 '09 at 5:26
Norman RamseyNorman Ramsey
184k5757 gold badges336336 silver badges517517 bronze badges
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What are “named tuples” in Python?
...xcept that they are immutable. They were added in Python 2.6 and Python 3.0, although there is a recipe for implementation in Python 2.4.
For example, it is common to represent a point as a tuple (x, y). This leads to code like the following:
pt1 = (1.0, 5.0)
pt2 = (2.5, 1.5)
from math import s...
What is the difference between ~> and >= when specifying rubygem in Gemfile?
... version provided and use that until it reaches a maximum version. So ~>0.8.5 is semantically equivalent to:
gem "cucumber", ">=0.8.5", "<0.9.0"
The easy way to think about it is that you're okay with the last digit incrementing to some arbitrary value, but the ones preceding it in the st...
Why are hexadecimal numbers prefixed with 0x?
Why are hexadecimal numbers prefixed as 0x ?
I understand the usage of the prefix but I don't understand the significance of why 0x was chosen.
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Emulating a do-while loop in Bash
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answered May 10 '13 at 19:59
jm666jm666
51k1414 gold badges8585 silver badges155155 bronze badges
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