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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
12
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C++ Dynamic Shared Library on Linux
...were for a plugin system, you would use MyClass as a base class and define all the required functions virtual. The plugin author would then derive from MyClass, override the virtuals and implement create_object and destroy_object. Your main application would not need to be changed in any way.
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Generating a PNG with matplotlib when DISPLAY is undefined
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Important note: .use needs to be called before pyplot is imported. So if you are, for instance, just trying to import pyplot, you need to import matplotlib first, call use, and than import pyplot.
– seaotternerd
Nov 8 '1...
TypeScript typed array usage
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You have an error in your syntax here:
this._possessions = new Thing[100]();
This doesn't create an "array of things". To create an array of things, you can simply use the array literal expression:
this._possessions = [];
Of the array constructor if you want to se...
Error in finding last used cell in Excel with VBA
...on.CountA(.Cells) <> 0 Then
lastrow = .Cells.Find(What:="*", _
After:=.Range("A1"), _
Lookat:=xlPart, _
LookIn:=xlFormulas, _
SearchOrder:=xlByRows, _
SearchDirection:=xlPrevio...
Why declare a struct that only contains an array in C?
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It allows you to pass the array to a function by value, or get it returned by value from a function.
Structs can be passed by value, unlike arrays which decay to a pointer in these contexts.
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Performance of Arrays vs. Lists
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Very easy to measure...
In a small number of tight-loop processing code where I know the length is fixed I use arrays for that extra tiny bit of micro-optimisation; arrays can be marginally faster if you use the indexer / for form - but IIRC believe it dep...
get list from pandas dataframe column
...rame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], inde...
How to measure time taken between lines of code in python?
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If you want to measure CPU time, can use time.process_time() for Python 3.3 and above:
import time
start = time.process_time()
# your code here
print(time.process_time() - start)
First call turns the timer on, and second call tells you how many seconds have elapsed.
The...
What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]
...terned. The
distinct values are stored in a string
intern pool.
Basically, a string intern pool allows a runtime to save memory by preserving immutable strings in a pool so that areas of the application can reuse instances of common strings instead of creating multiple instances of it.
As an ...