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Confusion between numpy, scipy, matplotlib and pylab
Numpy, scipy, matplotlib, and pylab are common terms among they who use python for scientific computation.
3 Answers
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How does Hadoop process records split across block boundaries?
...nteresting question, I spent some time looking at the code for the details and here are my thoughts. The splits are handled by the client by InputFormat.getSplits, so a look at FileInputFormat gives the following info:
For each input file, get the file length, the block size and calculate the spli...
Please explain the exec() function and its family
What is the exec() function and its family? Why is this function used and how does its work?
7 Answers
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Primary key/foreign Key naming convention [closed]
... group we have a raging debate regarding the naming convention for Primary and Foreign Keys. There's basically two schools of thought in our group:
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How to make a flat list out of list of lists?
...for item in sublist]
As evidence, you can use the timeit module in the standard library:
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l...
Simultaneously merge multiple data.frames in a list
... issue here is that each data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, I could merely rbind , for which plyr's rbind.fill would...
how do I make a single legend for many subplots with matplotlib?
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There is also a nice function get_legend_handles_labels() you can call on the last axis (if you iterate over them) that would collect everything you need from label= arguments:
handles, labels = ax.get_legend_handles_labels()
fig.legend(handles, labels, loc='upper c...
Logical Operators, || or OR?
... no "better" but the more common one is ||. They have different precedence and || would work like one would expect normally.
See also: Logical operators (the following example is taken from there):
// The result of the expression (false || true) is assigned to $e
// Acts like: ($e = (false || true...
Why fragments, and when to use fragments instead of activities?
In Android API 11+, Google has released a new class called Fragment .
11 Answers
11
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Is it possible to declare two variables of different types in a for loop?
...se a structured binding declaration. The syntax has been supported in gcc and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above...