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Should I use multiplication or division?
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Python:
time python -c 'for i in xrange(int(1e8)): t=12341234234.234 / 2.0'
real 0m26.676s
user 0m25.154s
sys 0m0.076s
time python -c 'for i in xrange(int(1e8)): t=12341234234.234 * 0.5'
real 0m17.932s
user 0m16.481s
sys 0m0.048s
multiplication is 33% faster
Lua:
time lua ...
How to navigate through a vector using iterators? (C++)
...tor to a vector of strings
int n = 3; // nth element to be found.
int i = 0; // counter.
// now start at from the beginning
// and keep iterating over the element till you find
// nth element...or reach the end of vector.
for(it = myvector.begin(); it != myvector.end(); it++,i++ ) {
// fou...
Python to print out status bar and percentage
...t progressbar
from time import sleep
bar = progressbar.ProgressBar(maxval=20, \
widgets=[progressbar.Bar('=', '[', ']'), ' ', progressbar.Percentage()])
bar.start()
for i in xrange(20):
bar.update(i+1)
sleep(0.1)
bar.finish()
To install it, you can use easy_install progressbar, or pip ...
MySQL - Get row number on select
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Take a look at this.
Change your query to:
SET @rank=0;
SELECT @rank:=@rank+1 AS rank, itemID, COUNT(*) as ordercount
FROM orders
GROUP BY itemID
ORDER BY ordercount DESC;
SELECT @rank;
The last select is your count.
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Golang: How to pad a number with zeros when printing?
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The fmt package can do this for you:
fmt.Printf("|%06d|%6d|\n", 12, 345)
Notice the 0 in %06d, that will make it a width of 6 and pad it with zeros. The second one will pad with spaces.
You can see it in action here: http://play.golang.org/p/cinDspMccp
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parseInt vs unary plus, when to use which?
..., here are a few differences I know of:
An empty string "" evaluates to a 0, while parseInt evaluates it to NaN. IMO, a blank string should be a NaN.
+'' === 0; //true
isNaN(parseInt('',10)); //true
The unary + acts more like parseFloat since it also accepts decimals.
parseInt on...
How can I find the length of a number?
...eparadox
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Remove border radius from Select tag in bootstrap 3
...arance: none;
-moz-appearance: none;
background-position: right 50%;
background-repeat: no-repeat;
background-image: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAA4AAAAMCAYAAABSgIzaAAAAGXRFWHRTb2Z0d2FyZQBBZG9iZSBJbWFnZVJlYWR5ccllPAAAAyJpVFh0WE1MOmNvbS5hZG9iZS54bXAAAAAAADw/e...
Django: Display Choice Value
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answered Dec 1 '10 at 5:36
jMylesjMyles
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Minimum and maximum date
...Javascript Date object. I found that the minimum date is something like 200000 B.C., but I couldn't get any reference about it.
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