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Is it possible to set a number to NaN or infinity?
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– David Heffernan
Mar 25 '11 at 22:30
2
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What is the easiest way to push an element to the beginning of the array?
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390
What about using the unshift method?
ary.unshift(obj, ...) → ary
Prepends objects to the...
How is Math.Pow() implemented in .NET Framework?
...king for an efficient approach for calculating a b (say a = 2 and b = 50 ). To start things up, I decided to take a look at the implementation of Math.Pow() function. But in .NET Reflector , all I found was this:
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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...
Selecting data frame rows based on partial string match in a column
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150
I notice that you mention a function %like% in your current approach. I don't know if that's a r...
What is “entropy and information gain”?
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1051
I assume entropy was mentioned in the context of building decision trees.
To illustrate, imag...
How to fix the uninitialized constant Rake::DSL problem on Heroku?
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205
Put this in your Rakefile above require 'rake':
require 'rake/dsl_definition'
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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...
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...
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...