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Why does Convert.ToString(null) return a different value if you cast null?
... compiler essentially tries to pick the most specific overload which will work with the input. A null value is convertible to any reference type. In this case string is more specific than object and hence it will be picked as the winner.
In the null as object you've solidified the type of the e...
Placing Unicode character in CSS content value [duplicate]
I have a problem. I have found the HTML code for the downwards arrow, ↓ (↓)
1 Answer
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Why do I get a SyntaxError for a Unicode escape in my file path?
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You need to use a raw string, double your slashes or use forward slashes instead:
r'C:\Users\expoperialed\Desktop\Python'
'C:\\Users\\expoperialed\\Desktop\\Python'
'C:/Users/expoperialed/Desktop/Python'
In regular python strings, the \U character combination signals a exte...
What's the canonical way to check for type in Python?
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To check if o is an instance of str or any subclass of str, use isinstance (this would be the "canonical" way):
if isinstance(o, str):
To check if the type of o is exactly str (exclude subclasses):
if type(o) is str:
The following also works, and can be u...
How to install latest version of git on CentOS 7.x/6.x
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You can use WANDisco's CentOS repository to install Git 2.x: for CentOS 6, for CentOS 7
Install WANDisco repo package:
yum install http://opensource.wandisco.com/centos/6/git/x86_64/wandisco-git-release-6-1.noarch.rpm
- or -
yum install http://opensource.wand...
OSGi, Java Modularity and Jigsaw
So as of yesterday morning I hadn't a clue as to what OSGi even was. OSGi was just some buzzword that I kept seeing cropping up over and over again, and so I finally set aside some time to brush up on it.
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Least common multiple for 3 or more numbers
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You can compute the LCM of more than two numbers by iteratively computing the LCM of two numbers, i.e.
lcm(a,b,c) = lcm(a,lcm(b,c))
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Different types of thread-safe Sets in Java
...readers and writers (though writing itself needs to be synchronized). The normally fast set operations (especially contains()) are quite slow here, as the arrays will be searched in linear time.
Use this only for really small sets which will be read (iterated) often and changed seldom. (Swings list...
Changing the “tick frequency” on x or y axis in matplotlib?
... marks with plt.xticks:
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
For example,
import numpy as np
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
plt.show()
(np.arange was used rather than Python's range funct...
How to check if running in Cygwin, Mac or Linux?
... Windows/Cygwin and Mac and Linux. It needs slightly different variables for each versions.
11 Answers
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