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open read and close a file in 1 line of code
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You don't really have to close it - Python will do it automatically either during garbage collection or at program exit. But as @delnan noted, it's better practice to explicitly close it for various reasons.
So, what you can do to keep ...
How to avoid warning when introducing NAs by coercion
... na = x %in% na.strings
x[na] = 0
x = as.numeric(x)
x[na] = NA_real_
x
}
as.num(c("1", "2", "X"), na.strings="X")
#[1] 1 2 NA
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Getting “unixtime” in Java
... platforms (and the year 2038 problem). 64-bit platforms use a larger time_t data type. Java dodged that bullet by using a long as the return for System.currentTimeMillis(). If you convert to int, you're re-introducing the year 2038 problem. See en.wikipedia.org/wiki/Year_2038_problem#Solutions
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How do I correctly clone a JavaScript object?
... if you know its name, but I don't know of any way to discover it automatically.
Yet another snag in the quest for an elegant solution is the problem of setting up the prototype inheritance correctly. If your source object's prototype is Object, then simply creating a new general object with {} wil...
Saving a Numpy array as an image
... Remember to scale the values to the right range for PNG, usually 0..255. The value ranges in neural networks are frequently 0..1 or -1..1.
– Tomáš Gavenčiak
Mar 31 '18 at 18:49
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UIViewContentModeScaleAspectFill not clipping
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If you want to expand your knowledge there is a really good article on how the iOS UIView stack is rendered. There is also a more in-depth article about the whole drawing pipeline.
In summary:
Rasterisation - All the view's content is rasterised (drawn or a offscreen pix...
How to get the name of enumeration value in Swift?
... on each case to return a string literal. In addition, this works automatically for any enum, even if no raw-value type is specified.
debugPrint(_:) & String(reflecting:) can be used for a fully-qualified name:
debugPrint(city)
// prints "App.City.Melbourne" (or similar, depending on the full ...
Python - Get path of root project structure
...to prevent directories with a common name, such as string, from unintentionally hiding valid modules that occur later on the module search path. In the simplest case, __init__.py can just be an empty file, but it can also execute initialization code for the package or set the __all__ variable, descr...
What is the purpose of the word 'self'?
...way that makes the instance to which the method belongs be passed automatically, but not received automatically: the first parameter of methods is the instance the method is called on. That makes methods entirely the same as functions, and leaves the actual name to use up to you (although self is th...
How to find the type of an object in Go?
... type we have access to the full reflection capabilities
type assertions - allows grouping types, for example recognize all int32, int64, uint32, uint64 types as "int"
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