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Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
I've just started learning Ruby and Ruby on Rails and came across validation code that uses ranges:
5 Answers
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Retain precision with double in Java
The above code prints:
22 Answers
22
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Creating dataframe from a dictionary where entries have different lengths
....x:
import pandas as pd
import numpy as np
d = dict( A = np.array([1,2]), B = np.array([1,2,3,4]) )
pd.DataFrame(dict([ (k,pd.Series(v)) for k,v in d.items() ]))
Out[7]:
A B
0 1 1
1 2 2
2 NaN 3
3 NaN 4
In Python 2.x:
replace d.items() with d.iteritems().
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Differences in boolean operators: & vs && and | vs ||
I know the rules for && and || but what are & and | ? Please explain these to me with an example.
11 Ans...
What is the printf format specifier for bool?
Since ANSI C99 there is _Bool or bool via stdbool.h . But is there also a printf format specifier for bool?
8 Answer...
numpy matrix vector multiplication [duplicate]
...ollowing normal matrix multiplication rules, a (n x 1) vector is expected, but I simply cannot find any information about how this is done in Python's Numpy module.
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How do I check if there are duplicates in a flat list?
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Use set() to remove duplicates if all values are hashable:
>>> your_list = ['one', 'two', 'one']
>>> len(your_list) != len(set(your_list))
True
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Behaviour of increment and decrement operators in Python
I notice that a pre-increment/decrement operator can be applied on a variable (like ++count ). It compiles, but it does not actually change the value of the variable!
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Determine font color based on background color
Given a system (a website for instance) that lets a user customize the background color for some section but not the font color (to keep number of options to a minimum), is there a way to programmatically determine if a "light" or "dark" font color is necessary?
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Virtual member call in a constructor
I'm getting a warning from ReSharper about a call to a virtual member from my objects constructor.
18 Answers
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