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Fastest way to reset every value of std::vector to 0
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edited Apr 21 '17 at 9:20
Qix - MONICA WAS MISTREATED
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Double vs. BigDecimal?
... has a certain precision. Working with doubles of various magnitudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, a...
Find the max of two or more columns with pandas
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You can get the maximum like this:
>>> import pandas as pd
>>> df = pd.Data...
How to initialize an array's length in JavaScript?
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18 Answers
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From ND to 1D arrays
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Use np.ravel (for a 1D view) or np.ndarray.flatten (for a 1D copy) or np.ndarray.flat (for an 1D iterator):
In [12]: a = np.array([[1,2,3], [4,5,6]])
In [13]: b = a.ravel()
In [14]: b
Out[14]: array([1, 2, 3, 4, 5, 6])
Note that ravel() ret...
pyplot scatter plot marker size
...d the output they produce.
# doubling the width of markers
x = [0,2,4,6,8,10]
y = [0]*len(x)
s = [20*4**n for n in range(len(x))]
plt.scatter(x,y,s=s)
plt.show()
gives
Notice how the size increases very quickly. If instead we have
# doubling the area of markers
x = [0,2,4,6,8,10]
y = [0]*len(...
How many double numbers are there between 0.0 and 1.0?
...or example, that's the number of distinct doubles between 0.5 included and 1.0 excluded, and exactly that many also lie between 1.0 included and 2.0 excluded, and so forth.
Counting the doubles between 0.0 and 1.0 is harder than doing so between powers of two, because there are many powers of two i...
How can I sort arrays and data in PHP?
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Sort a list by multiple attributes?
... can be a function that returns a tuple:
s = sorted(s, key = lambda x: (x[1], x[2]))
Or you can achieve the same using itemgetter (which is faster and avoids a Python function call):
import operator
s = sorted(s, key = operator.itemgetter(1, 2))
And notice that here you can use sort instead of...
Git Extensions: Win32 error 487: Couldn't reserve space for cygwin's heap, Win32 error 0
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