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Python 3 turn range to a list
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You can just construct a list from the range object:
my_list = list(range(1, 1001))
This is how you do it with generators in python2.x as well. Typically speaking, you probably don't need a list though since you can come by the value of my_list[i] more efficiently (i + 1), and...
Check if all elements in a list are identical
...for very large arrays, a native solution which optimizes away calls to obj.__eq__ when lhs is rhs, and out-of-order optimizations to allow short circuiting sorted lists more quickly.
– Glenn Maynard
Oct 2 '10 at 8:31
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surface plots in matplotlib
...a surface.
Here's a smooth surface example:
import numpy as np
from mpl_toolkits.mplot3d import Axes3D
# Axes3D import has side effects, it enables using projection='3d' in add_subplot
import matplotlib.pyplot as plt
import random
def fun(x, y):
return x**2 + y
fig = plt.figure()
ax = fi...
How to open link in new tab on html?
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Set the 'target' attribute of the link to _blank:
<a href="#" target="_blank" rel="noopener noreferrer">Link</a>
Edit: for other examples, see here: http://www.w3schools.com/tags/att_a_target.asp
(Note: I previously suggested blank instead of _blank beca...
Pretty-print an entire Pandas Series / DataFrame
I work with Series and DataFrames on the terminal a lot. The default __repr__ for a Series returns a reduced sample, with some head and tail values, but the rest missing.
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What is a memory fence?
...annot cache the variable value. The Linux kernel uses a gcc extension (asm __volatile__("": : :"memory")) to create a full compiler optimization barrier.
– CesarB
Nov 13 '08 at 10:36
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How to call a parent method from child class in javascript?
...cessing the parent constructor's prototype methods is possible through the __proto__ property (I am pretty sure there will be fellow JS coders to complain that it's depreciated) which is depreciated but at the same time discovered that it is actually an essential tool for sub-classing needs (especia...
How to maintain aspect ratio using HTML IMG tag
...img src="https://upload.wikimedia.org/wikipedia/meta/0/08/Wikipedia-logo-v2_1x.png">
</div>
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private[this] vs private
...nt type T occurs in contravariant position in type Option[T] of value value_=
class Holder[+T] (initialValue: Option[T]) {
This error occurs because value is a mutable variable on the covariant type T (+T) which is normally a problem unless marked as private to the instance with private[this...
Python: changing value in a tuple
...nvert back, or construct a new tuple by concatenation.
In [1]: def replace_at_index1(tup, ix, val):
...: lst = list(tup)
...: lst[ix] = val
...: return tuple(lst)
...:
In [2]: def replace_at_index2(tup, ix, val):
...: return tup[:ix] + (val,) + tup[ix+1:]
...:
S...