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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?
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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?
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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...
Targeting both 32bit and 64bit with Visual Studio in same solution/project
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Yes, you can target both x86 and x64 with the same code base in the same project. In general, things will Just Work if you create the right solution configurations in VS.NET (although P/Invoke to entirely unmanaged DLLs will most likely require some ...
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
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>>> inspect.isclass(X)
True
>>> x = X()
>>> isinstance(x, X)
True
>>> y = 25
>>> isinstance(y, X)
False
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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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Normalize data in pandas
...0.932785 4.535396 0.598124
In [93]: df_norm = (df - df.mean()) / (df.max() - df.min())
In [94]: df_norm
Out[94]:
a b c d
A 0.085789 -0.394348 0.337016 -0.109935
B -0.463830 0.164926 -0.650963 0.256714
C -0.158129 0.605652 -0.035090 -0.573389
D 0.536170 -0...
Use of 'prototype' vs. 'this' in JavaScript?
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The examples have very different outcomes.
Before looking at the differences, the following should be noted:
A constructor's prototype provides a way to share methods and values among instances via the instance's private [[Prot...