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Understanding generators in Python
...A generator is simply a function which returns an object on which you can call next, such that for every call it returns some value, until it raises a StopIteration exception, signaling that all values have been generated. Such an object is called an iterator.
Normal functions return a single value...
PHP: exceptions vs errors?
...
Exceptions are thrown - they are intended to be caught. Errors are generally unrecoverable. Lets say for instance - you have a block of code that will insert a row into a database. It is possible that this call fails (duplicate ID) - you will want to have a "Error" which in this case is an "Exc...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
Uninstall Node.JS using Linux command line?
How do you uninstall node.js using the cmd line in linux?
14 Answers
14
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Convert string to binary in python
...encoding.
In Python 3, then, you can do something like this:
a = "test"
a_bytes = bytes(a, "ascii")
print(' '.join(["{0:b}".format(x) for x in a_bytes]))
The differences between UTF-8 and ascii encoding won't be obvious for simple alphanumeric strings, but will become important if you're process...
How to use a custom comparison function in Python 3?
...e a workaround, but I think I am going to lose some performance by passing all the comparison operators < > = to middle man, since my original custom sort is written in C , it had around 1/2x speed of default sort.
– YOU
Mar 28 '10 at 5:26
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What is the difference between map and flatMap and a good use case for each?
...ark-shell session:
First, some data - two lines of text:
val rdd = sc.parallelize(Seq("Roses are red", "Violets are blue")) // lines
rdd.collect
res0: Array[String] = Array("Roses are red", "Violets are blue")
Now, map transforms an RDD of length N into another RDD of length N.
For examp...
Exif manipulation library for python [closed]
...mation from Jpeg and Tiff files which include it. This information is typically included in images created using digital imaging devices such as digital cameras, digital film scanners, etc.
However, it looks like pyexif hasn't been updated in quite while. They recommend if theirs isn't doing the ...
What is the difference between range and xrange functions in Python 2.X?
...hey did. In Python 3. (They couldn't do that in the Python 2.x line, since all changes must be backwards compatible.)
– Paul Draper
May 7 '15 at 3:50
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Scala how can I count the number of occurrences in a list
...", "banana", "apple", "oranges", "oranges")
s.groupBy(identity).mapValues(_.size)
giving a Map with a count for each item in the original sequence:
Map(banana -> 1, oranges -> 3, apple -> 3)
The question asks how to find the count of a specific item. With this approach, the solution w...