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How to use filter, map, and reduce in Python 3
filter , map , and reduce work perfectly in Python 2. Here is an example:
7 Answers
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What is the best way to use a HashMap in C++?
I know that STL has a HashMap API, but I cannot find any good and thorough documentation with good examples regarding this.
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How to URL encode a string in Ruby
...m , it is more intellectual working with urls.
– Alexander.Iljushkin
Oct 13 '15 at 19:46
I needed to access files on r...
Remove all occurrences of a value from a list?
... I wouldn't call this solution the best. List comprehensions are faster and easier to understand while skimming through code. This would rather be more of a Perl way than Python.
– Peter Nimroot
Aug 13 '16 at 15:25
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Geometric Mean: is there a built-in?
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Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...
Understanding the Use of ColorMatrix and ColorMatrixColorFilter to Modify a Drawable's Hue
I'm working on a UI for an app, and I'm attempting to use grayscale icons, and allow the user to change the theme to a color of their choosing. To do this, I'm trying to just apply a ColorFilter of some sort to overlay a color on top of the drawable. I've tried using PorterDuff.Mode.MULTIPLY, and it...
How do I compute derivative using Numpy?
...es
Automatic Derivatives
Symbolic Differentiation
Compute derivatives by hand.
Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.
Symbolic differentiation is ideal if your problem is simple enough. Symbolic...
Equation for testing if a point is inside a circle
If you have a circle with center (center_x, center_y) and radius radius , how do you test if a given point with coordinates (x, y) is inside the circle?
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Select the values of one property on all objects of an array in PowerShell
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I think you might be able to use the ExpandProperty parameter of Select-Object.
For example, to get the list of the current directory and just have the Name property displayed, one would do the following:
ls | select -Property Name
This is still returning Direc...
RSA Public Key format
...ers from ---- BEGIN SSH2 PUBLIC KEY ---- to -----BEGIN RSA PUBLIC KEY----- and expect that it will be sufficient to convert from one format to another (which is what you've done in your example).
This article has a good explanation about both formats.
What you get in an RSA PUBLIC KEY is closer to...