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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(...
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...
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...
How to initialize an array's length in JavaScript?
...
18 Answers
18
Active
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Why is January month 0 in Java Calendar?
In java.util.Calendar , January is defined as month 0, not month 1. Is there any specific reason to that ?
16 Answers
...
Initialising an array of fixed size in python [duplicate]
...
11 Answers
11
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How to count the number of true elements in a NumPy bool array
...:
>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is a bool...
Why does parseInt(1/0, 19) return 18?
...
1294
The result of 1/0 is Infinity.
parseInt treats its first argument as a string which means fi...
What is Weak Head Normal Form?
...
These expressions are all in normal form:
42
(2, "hello")
\x -> (x + 1)
These expressions are not in normal form:
1 + 2 -- we could evaluate this to 3
(\x -> x + 1) 2 -- we could apply the function
"he" ++ "llo" -- we could apply the (++)
(1 + 1, 2 + 2) ...
How to catch integer(0)?
...
164
That is R's way of printing a zero length vector (an integer one), so you could test for a bei...