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How to enable PHP short tags?
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We have a PHP coding test and occasionally receive submissions where the <?= short tag has been used. Unfortunately the assumption that this style is in use everywhere is a little naive and often comes from developers brought up on a diet of ASP. Clearly it is...
pandas DataFrame: replace nan values with average of columns
...amount imputed for the mean using this?
– bernando_vialli
Jun 8 '18 at 14:29
25
Instead of df=df....
What are the differences between vector and list data types in R?
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Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
Passing a method as a parameter in Ruby
...ightedknn(data, vec1, k = 5, weightf = gaussian)
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weight = weightf.call(dist)
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end
Just note that you can't set a default argument in a block declaration like that. So you need to use a splat and setup the default in the proc code itself.
Or, depending on your scope of all this, it...
Method Syntax in Objective-C
...I on the iPhone) is being returned. From my understanding, the Method is called ' pickerView ', and returns an NSInteger.
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javascript set a variable if undefined
... x === 'undefined') ? your_default_value : x;
On newer browsers it's actually safe to write:
var x = (x === undefined) ? your_default_value : x;
but be aware that it is possible to subvert this on older browsers where it was permitted to declare a variable named undefined that has a defined val...
Validate that a string is a positive integer
...nclude 0, even though 0 is not positive. I include notes if you want to disallow 0.
Based on Parsing
If you want it to be a normalized decimal integer string over a reasonable range of values, you can do this:
function isNormalInteger(str) {
var n = Math.floor(Number(str));
return n !== I...
What is the difference between procedural programming and functional programming? [closed]
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A functional language (ideally) allows you to write a mathematical function, i.e. a function that takes n arguments and returns a value. If the program is executed, this function is logically evaluated as needed.1
A procedural language, on the other ...
Utilizing the GPU with c# [closed]
...OpenTK -- dead/Cloo) - many of these are just bindings - ie enable you to call the GPU from C#, but your kernel code (code which is actually run on the GPU) needs to be written in C or OpenCL, meaning you must use (and learn) another language.
As I said, I would recommend Cudafy over all the other...
Getting a list of files in a directory with a glob
...ing operations for you. The functions and types are declared in a header called glob.h, so you'll need to #include it. If open up a terminal an open the man page for glob by typing man 3 glob you'll get all of the information you need to know to use the functions.
Below is an example of how you c...