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How can I remove an element from a list?
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I don't know R at all, but a bit of creative googling led me here: http://tolstoy.newcastle.edu.au/R/help/05/04/1919.html
The key quote from there:
I do not find explicit documentation for R on how to remove elements from lists, but trial and ...
How to use base class's constructors and assignment operator in C++?
I have a class B with a set of constructors and an assignment operator.
5 Answers
5
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Create nice column output in python
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data = [['a', 'b', 'c'], ['aaaaaaaaaa', 'b', 'c'], ['a', 'bbbbbbbbbb', 'c']]
col_width = max(len(word) for row in data for word in row) + 2 # padding
for row in data:
print "".join(word.ljust(col_width) for word in row)
a ...
Convert Array to Object
What is the best way to convert:
45 Answers
45
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Is there a difference between “==” and “is”?
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is will return True if two variables point to the same object, == if the objects referred to by the variables are equal.
>>> a = [1, 2, 3]
>>> b = a
>>> b is a
True
>>> b == a
True
# Make a new copy of list `a` via the...
How does java do modulus calculations with negative numbers?
Am I doing modulus wrong? Because in Java -13 % 64 is supposed to evaluate to -13 but I get 51 .
14 Answers
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What is the easiest way to remove the first character from a string?
...t;> "12,23,987,43"
I'm always looking for the fastest and most readable way of doing things:
require 'benchmark'
N = 1_000_000
puts RUBY_VERSION
STR = "[12,23,987,43"
Benchmark.bm(7) do |b|
b.report('[0]') { N.times { "[12,23,987,43"[0] = '' } }
b.report('sub') { N.times { "[12,23,98...
How can I force division to be floating point? Division keeps rounding down to 0?
I have two integer values a and b , but I need their ratio in floating point. I know that a < b and I want to calculate a / b , so if I use integer division I'll always get 0 with a remainder of a .
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What is the difference between “git branch” and “git checkout -b”?
I used git checkout -b to create a new branch. I think that git branch does the same thing.
How do these two commands differ, if they differ at all?
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How do I merge changes to a single file, rather than merging commits?
I have two branches (A and B) and I want to merge a single file from branch A with a corresponding single file from Branch B.
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