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A simple explanation of Naive Bayes Classification
...les, would receive misleadingly high scores.
In general, for an example, 70% of our data can be used as training set cases. Also remember to partition the original set into the training and test sets randomly.
Now I come to your other question about Naive Bayes.
To demonstrate the concept of Naï...
Is it possible to set a number to NaN or infinity?
...
– David Heffernan
Mar 25 '11 at 22:30
2
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Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
Is it guaranteed that False == 0 and True == 1 , in Python (assuming that they are not reassigned by the user)? For instance, is it in any way guaranteed that the following code will always produce the same results, whatever the version of Python (both existing and, likely, future ones)?
...
Why does 0.ToString(“#.##”) return an empty string instead of 0.00 or at least 0?
Why does 0.ToString("#.##") return an empty string? Shouldn't it be 0.00 or at least 0 ?
5 Answers
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Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
...
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You need to specify data, index and columns to DataFrame constructor, as in:
>>> pd.Da...
Fastest way to reset every value of std::vector to 0
...at's the fastest way to reset every value of a std::vector<int> to 0 and keeping the vectors initial size ?
6 Answ...
Numpy - add row to array
...pare its row to a number: i < 3?
EDIT after OP's comment:
A = array([[0, 1, 2], [0, 2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X where the first element < 3:
import numpy as np
A = np.vstack((A, X[X[:,0] < 3]))
# returns:
array([[0, 1, 2],
...
How can you profile a Python script?
...e.bat':
python -m cProfile %1
So all I have to do is run:
profile euler048.py
And I get this:
1007 function calls in 0.061 CPU seconds
Ordered by: standard name
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.000 0.000 0.061 0.061 <string>:1(&lt...
How to calculate the angle between a line and the horizontal axis?
... the positive Y axis at P1).
angleInDegrees = arctan(deltaY / deltaX) * 180 / PI
But arctan may not be ideal, because dividing the differences this way will erase the distinction needed to distinguish which quadrant the angle is in (see below). Use the following instead if your language includes ...
Days between two dates? [duplicate]
...er of days:
>>> from datetime import date
>>> a = date(2011,11,24)
>>> b = date(2011,11,17)
>>> a-b
datetime.timedelta(7)
>>> (a-b).days
7
And it works with datetimes too — I think it rounds down to the nearest day:
>>> from datetime import...