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What is memoization and how can I use it in Python?
...orials using memoization in Python would be something like this:
factorial_memo = {}
def factorial(k):
if k < 2: return 1
if k not in factorial_memo:
factorial_memo[k] = k * factorial(k-1)
return factorial_memo[k]
You can get more complicated and encapsulate the memoization...
Adjust UILabel height to text
...ne about some println's or just a line with only comments (then it says EXC_BAD_ACCESS code=2 as well)
– TheBurgerShot
Aug 8 '14 at 11:52
6
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How do I query between two dates using MySQL?
...querying between September 29 2010 and January 30 2010). Try reversing the order of the dates:
SELECT *
FROM `objects`
WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55')
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adding noise to a signal in python
...umpy as np
import matplotlib.pyplot as plt
t = np.linspace(1, 100, 1000)
x_volts = 10*np.sin(t/(2*np.pi))
plt.subplot(3,1,1)
plt.plot(t, x_volts)
plt.title('Signal')
plt.ylabel('Voltage (V)')
plt.xlabel('Time (s)')
plt.show()
x_watts = x_volts ** 2
plt.subplot(3,1,2)
plt.plot(t, x_watts)
plt.title...
How to implement an abstract class in ruby?
...clarative about which methods are abstract:
module Abstract
def abstract_methods(*args)
args.each do |name|
class_eval(<<-END, __FILE__, __LINE__)
def #{name}(*args)
raise NotImplementedError.new("You must implement #{name}.")
end
END
# import...
Can iterators be reset in Python?
...r protocol is very simple, and only provides one single method (.next() or __next__()), and no method to reset an iterator in general.
The common pattern is to instead create a new iterator using the same procedure again.
If you want to "save off" an iterator so that you can go back to its beginni...
How can I determine if a JavaScript variable is defined in a page? [duplicate]
...
To avoid accidental assignment, I make a habit of reversing the order of the conditional expression:
if ('undefined' !== typeof x) {
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How to replace captured groups only?
...ding and following text:
str.replace(/(.*name="\w+)(\d+)(\w+".*)/, "$1!NEW_ID!$3")
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Missing include “bits/c++config.h” when cross compiling 64 bit program on 32 bit in Ubuntu
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While compiling in RHEL 6.2 (x86_64), I installed both 32bit and 64bit libstdc++-dev packages, but I had the "c++config.h no such file or directory" problem.
Resolution:
The directory /usr/include/c++/4.4.6/x86_64-redhat-linux was missing.
I did the foll...
UITextView that expands to text using auto layout
...nstraint for UITextView's height, and I saved it in an instance variable.
_descriptionHeightConstraint = [NSLayoutConstraint constraintWithItem:_descriptionTextView
attribute:NSLayoutAttributeHeight
relatedBy:NSLayoutRelationEqual
...