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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...
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...
How can I run just the statement my cursor is on in SQL Server Management Studio?
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This worked really well for me in SSMS2012, but now I'm running SSMS2014 and I really miss it! Anyone know of a SSMS2014 solution?
– samp
May 11 '15 at 21:01
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Comparison of CI Servers? [closed]
...oyments, functional tests, etc. To help with that planning I created this wallchart on the Elements of Enterprise CI (PDF; no registration required). Please don't let the "E-word" put you off; I just mean stuff beyond the basic fast feedback CI build. :)
It isn't tool specific but lists a variety o...
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 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 ...
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...