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How to define a two-dimensional array?
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1039
You're technically trying to index an uninitialized array. You have to first initialize the ou...
Plot a legend outside of the plotting area in base graphics?
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10 Answers
10
Active
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How can I check if a string represents an int, without using try/except?
...t;> print RepresentsInt("+123")
True
>>> print RepresentsInt("10.0")
False
It's going to be WAY more code to exactly cover all the strings that Python considers integers. I say just be pythonic on this one.
sh...
What does the ^ operator do in Java?
...perator.
Let's take 5^6 as example:
(decimal) (binary)
5 = 101
6 = 110
------------------ xor
3 = 011
This the truth table for bitwise (JLS 15.22.1) and logical (JLS 15.22.2) xor:
^ | 0 1 ^ | F T
--+----- --+-----
0 | 0 1 F | F T
1 | 1 0 T | T...
How to format a number as percentage in R?
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10 Answers
10
Active
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List of lists changes reflected across sublists unexpectedly
...rences to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 140560897920048
print(
f"id(l[0]): {id(l[0])}\n"
f"id(l[1]): {id(l[1])}\n"
f"id(l[2]): {id(l[2])}"
)
# id(l[0]): 140560897920048
# id(l[1]): 140560897920048
# id(l[2]): 140560897920048
x[0] = 42
print(f"x: {x}")
# ...
Extracting specific columns in numpy array
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edited Aug 23 at 10:39
cs95
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answere...
How to check BLAS/LAPACK linkage in NumPy and SciPy?
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edited Dec 16 '19 at 11:30
Demi-Lune
1,22822 gold badges1010 silver badges1919 bronze badges
answered O...
Check if at least two out of three booleans are true
...the real world :)
– Juliet
Jun 19 '10 at 16:02
124
@Juliet: I don't know, I think if this was a r...
Regular expression to match DNS hostname or IP Address?
...or by combining them in a joint OR expression.
ValidIpAddressRegex = "^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$";
ValidHostnameRegex = "^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Z...