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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...
Amazon S3 boto - how to create a folder?
...y S3 access tools like S3Fox show like a directory structure, but it's actually just a single file in a bucket.
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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...
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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Bogus foreign key constraint fail
...each query (bugs.mysql.com/bug.php?id=8280), making it neccessary to write all the drop statements in one query, eg.
SET FOREIGN_KEY_CHECKS=0;
DROP TABLE my_first_table_to_drop;
DROP TABLE my_second_table_to_drop;
SET FOREIGN_KEY_CHECKS=1;
Where the SET FOREIGN_KEY_CHECKS=1 serves as an extr...
How to convert string to boolean php
...ted by @lauthiamkok in the comments. I'm posting it here as an answer to call more attention to it.
Depending on your needs, you should consider using filter_var() with the FILTER_VALIDATE_BOOLEAN flag.
filter_var( true, FILTER_VALIDATE_BOOLEAN); // true
filter_var( 'true', FILTER_VALIDATE_...
How to add text inside the doughnut chart using Chart.js?
...ext based off the amount of text and the size of the doughnut. Here is a small script you can use to dynamically place any amount of text in the middle, and it will automatically resize it.
Example: http://jsfiddle.net/kdvuxbtj/
It will take any amount of text in the doughnut sized perfect for ...
Check if object is a jQuery object
...
isn't obj.__proto__.jquery instead of obj.constructor.prototype.jquery enough? just a bit short :)
– Axel
Jul 3 '17 at 9:35
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Check whether an array is empty [duplicate]
...pty($errors)) {
}
array_filter() function's default behavior will remove all values from array which are equal to null, 0, '' or false.
Otherwise in your particular case empty() construct will always return true if there is at least one element even with "empty" value.
...
How to replace captured groups only?
...ding and following text:
str.replace(/(.*name="\w+)(\d+)(\w+".*)/, "$1!NEW_ID!$3")
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