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Way to get number of digits in an int?
...See my benchmark unit test below(wich may be flawed too i am no benchmark expert). Over a large number of runs (100 000 000), the speed is 11s to 8s on my machine hardly twice as fast.
– Jean
Aug 20 '09 at 15:36
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How to overwrite the previous print to stdout in python?
...') character to return to the start of the line without advancing to the next line:
for x in range(10):
print '{0}\r'.format(x),
print
The comma at the end of the print statement tells it not to go to the next line. The last print statement advances to the next line so your prompt won't overwri...
Qt: can't find -lGL error
...he error and in libgl1-... is for OpenGL, a fundamental dependency of Qt 5.x. This is a common error for devs when setting up for Qt development -- but once they install the OpenGL development lib they never see it again.
– pixelgrease
Jun 4 '15 at 23:04
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Scatter plot and Color mapping in Python
I have a range of points x and y stored in numpy arrays.
Those represent x(t) and y(t) where t=0...T-1
3 Answers
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What is Weak Head Normal Form?
...
I'll try to give an explanation in simple terms. As others have pointed out, head normal form does not apply to Haskell, so I will not consider it here.
Normal form
An expression in normal form is fully evaluated, and no sub-expression could be...
How do I use arrays in C++?
...t of an array, there is no way to detect how large that array is or where exactly the pointer points to relative to the bounds of the array. Pointers are extremely stupid.
Arrays are not pointers
The compiler will silently generate a pointer to the first element of an array whenever it is deemed u...
What does -> mean in Python function definitions?
...
It's a function annotation.
In more detail, Python 2.x has docstrings, which allow you to attach a metadata string to various types of object. This is amazingly handy, so Python 3 extends the feature by allowing you to attach metadata to functions describing their parameters an...
I want to get the type of a variable at runtime
...ble" is always present, and can be passed around as a type parameter. For example:
val x = 5
def f[T](v: T) = v
f(x) // T is Int, the type of x
But depending on what you want to do, that won't help you. For instance, may want not to know what is the type of the variable, but to know if the type o...
How to check whether a variable is a class or not?
... inspect.isclass function.
>>> import inspect
>>> class X(object):
... pass
...
>>> inspect.isclass(X)
True
>>> x = X()
>>> isinstance(x, X)
True
>>> y = 25
>>> isinstance(y, X)
False
...
Split column at delimiter in data frame [duplicate]
... split one column into two within at data frame based on a delimiter. For example,
6 Answers
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