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MySQL Query GROUP BY day / month / year
..._date), MONTH(record_date), COUNT(*)
FROM stats
GROUP BY YEAR(record_date)*100 + MONTH(record_date)
I compared these versions on a big table with 1,357,918 rows (innodb),
and the 2nd version appears to have better results.
version1 (average of 10 executes): 1.404 seconds
version2 (average of 10...
How to calculate the SVG Path for an arc (of a circle)
...e
document.getElementById("arc1").setAttribute("d", describeArc(200, 400, 100, 0, 180));
and in your html
<path id="arc1" fill="none" stroke="#446688" stroke-width="20" />
Live demo
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Most efficient way to store thousand telephone numbers
...f phone numbers for which the first m bits are 1...11 - this last count is 1000(decimal). There are 2^m such counts and each count is at most 1000. If we omit the last one (because we know it is 1000 anyway), we can store all of these numbers in a contiguous block of (2^m - 1) * 10 bits. (10 bits is...
Warning message: In `…` : invalid factor level, NA generated
... of 2 variables:
$ Type : Factor w/ 1 level "": NA 1 1
$ Amount: chr "100" "0" "0"
>
> fixed <- data.frame("Type" = character(3), "Amount" = numeric(3),stringsAsFactors=FALSE)
> fixed[1, ] <- c("lunch", 100)
> str(fixed)
'data.frame': 3 obs. of 2 variables:
$ Type : chr ...
Create an empty object in JavaScript with {} or new Object()?
... Array(); over []; - with one minor exception:
var emptyArray = new Array(100);
creates a 100 item long array with all slots containing undefined - which may be nice/useful in certain situations (such as (new Array(9)).join('Na-Na ') + 'Batman!').
My recommendation
Never use new Object(); - i...
Java switch statement multiple cases
...l the time:
switch (variable)
{
case 5:
case 6:
etc.
case 100:
doSomething();
break;
}
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How do I create a nice-looking DMG for Mac OS X using command-line tools?
...ner window to false
set the bounds of container window to {400, 100, 885, 430}
set theViewOptions to the icon view options of container window
set arrangement of theViewOptions to not arranged
set icon size of theViewOptions to 72
set background...
Join a list of strings in python and wrap each string in quotation marks
...t;> timeit.Timer("""words = ['hello', 'world', 'you', 'look', 'nice'] * 100; ', '.join('"{0}"'.format(w) for w in words)""").timeit(1000)
0.32559704780578613
>>> timeit.Timer("""words = ['hello', 'world', 'you', 'look', 'nice'] * 100; '"{}"'.format('", "'.join(words))""").timeit(1000)
0...
Maintaining the final state at end of a CSS3 animation
...fter animation ends. for example if your animation changes width from 0 to 100px, this property makes sure the element remains 100px wide after animation ends.
– Farzad YZ
Feb 17 '16 at 15:23
...
How to clear the interpreter console?
...
Well, here's a quick hack:
>>> clear = "\n" * 100
>>> print clear
>>> ...do some other stuff...
>>> print clear
Or to save some typing, put this file in your python search path:
# wiper.py
class Wipe(object):
def __repr__(self):
...