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How to convert a table to a data frame
...rs, another way I've used is data.frame(rbind(mytable)). Using the example from @X.X:
> freq_t = table(cyl = mtcars$cyl, gear = mtcars$gear)
> freq_t
gear
cyl 3 4 5
4 1 8 2
6 2 4 1
8 12 0 2
> data.frame(rbind(freq_t))
X3 X4 X5
4 1 8 2
6 2 4 1
8 12 0 2
If t...
Convert Elixir string to integer or float
...
There are 4 functions to create number from string
String.to_integer, String.to_float
Integer.parse, Float.parse
String.to_integer works nicely but String.to_float is tougher:
iex()> "1 2 3 10 100" |> String.split |> Enum.map(&String.to_integer/1)
[...
Check if a variable is of function type
...ence, except instanceof won't work if you're checking a function that came from another document (an iframe, maybe). Performance varies.
– rvighne
Feb 1 '14 at 0:18
11
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unique object identifier in javascript
...hold strong references to the objects you pass into it. This prevents them from being garbage collected and is a major memory leak
– Downgoat
Aug 18 at 8:35
add a comment
...
Developing for Android in Eclipse: R.java not regenerating
.... I find that often I change a string and forget to change the string name from AndroidManifest.xml.
Check that Android SDK Build-tools is installed. Window -> Android SDK Manager -> Tools -> Android SDK Build-tools
Make sure when you update the Android SDK Tools, you also update the Androi...
How to return a part of an array in Ruby?
...turns a subarray specified by range. Negative indices count
backward from the end of the array (-1 is the last element).
Returns nil if the index (or starting index) are out of range.
a = [ "a", "b", "c", "d", "e" ]
a[2] + a[0] + a[1] #=> "cab"
a[6] ...
Make sure that the controller has a parameterless public constructor error
...r all root types explicitly.
But of course, the configuration error comes from you adding the second constructor to your DbContext. Unity always tries to pick the constructor with the most arguments, but it has no idea how to resolve this particular constructor.
So the real cause is that you are t...
Rails 4: how to use $(document).ready() with turbo-links
... instead of "page:load", as the former is fired whether the page is loaded from the server or from client-side cache.
– Nathan Long
Apr 28 '15 at 14:22
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...
What are the Dangers of Method Swizzling in Objective-C?
...even realise the swizzle has been preformed. If there are bugs introduced from the swizzle (perhaps dues to changes in the original class) they will be hard to resolve.
In summary, you should keep swizzling to a minimum and consider how changes in the original class might effect your swizzle. Al...
Inputting a default image in case the src attribute of an html is not valid?
...ebsite for compatibility. This element is widely supported by all browsers from IE6+.
* Unless the URL for the image changed (again), in which case you'll probably see the alt text.
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