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What is the difference between BIT and TINYINT in MySQL?
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answered Nov 14 '08 at 14:39
Robert GambleRobert Gamble
94.3k2121 gold badges139139 silver badges135135 bronze badges
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What is the Ruby (spaceship) operator?
...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument.
a <=> b :=
if a < b t...
How to create a video from images with FFmpeg?
...video filter instead of -r for the output framerate
ffmpeg -r 1/5 -i img%03d.png -c:v libx264 -vf fps=25 -pix_fmt yuv420p out.mp4
Alternatively the format video filter can be added to the filter chain to replace -pix_fmt yuv420p like "fps=25,format=yuv420p". The advantage of this method is th...
Bootstrap carousel multiple frames at once
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20
Can this be done with bootstrap 3's carousel? I'm hoping I won't have
to go hunting for yet...
Java String - See if a string contains only numbers and not letters
...Z]+") == false && text.length() > 2){
to:
if (text.matches("[0-9]+") && text.length() > 2) {
Instead of checking that the string doesn't contain alphabetic characters, check to be sure it contains only numerics.
If you actually want to use the numeric value, use Integer.p...
Is SQL or even TSQL Turing Complete?
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Qantas 94 Heavy
14.4k1616 gold badges6060 silver badges7777 bronze badges
answered Sep 28 '11 at 7:59
Jan de VosJan de Vos
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ValueError: math domain error
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edited Sep 3 '17 at 20:49
answered Apr 8 '13 at 23:06
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Best way of returning a random boolean value
...alse].sample is faster than rand(2) == 1. When I performed each operation 10 million times the rand method was 2.179s. The sample method was 1.645s.
– Mirror318
Jun 27 '16 at 4:47
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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
Creating a CSS3 box-shadow on all sides but one
...paddings) and add shadow
#content {
font-size: 1.8em;
box-shadow: 0 0 8px 2px #888; /* line shadow */
}
add shadows to tabs:
#nav li a {
margin-left: 20px;
padding: .7em .5em .5em .5em;
font-size: 1.3em;
color: #FFF;
display: inline-block;
text-transform: uppercas...