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How do you know when to use fold-left and when to use fold-right?
...re you can see the traversal to the base case 4 and building up the result from there.
So I posit a rule of thumb: if it looks like a list iteration, one that would be simple to write in tail-recursive form, foldl is the way to go.
But really this will be probably be most evident from the associat...
Executing periodic actions in Python [duplicate]
...o precision of the time module (unlike several of the solutions I've tried from stack exchange).
Note: for Python 2.x, replace next(g) below with g.next().
import time
def do_every(period,f,*args):
def g_tick():
t = time.time()
while True:
t += period
yie...
How to append contents of multiple files into one file
...d doing it using cp for each file. But that overwrites the contents copied from the previous file. I also tried
10 Answers...
Splitting a list into N parts of approximately equal length
...her than chunks of n:
def chunks(l, n):
""" Yield n successive chunks from l.
"""
newn = int(len(l) / n)
for i in xrange(0, n-1):
yield l[i*newn:i*newn+newn]
yield l[n*newn-newn:]
l = range(56)
three_chunks = chunks (l, 3)
print three_chunks.next()
print three_chunks.ne...
Deploy a project using Git push
... Make sure you have a .htaccess policy that protects the .git directory from being read. Somebody who feels like URL diving could have a field day with the entire source code if it's accessible.
– Jeff Ferland
May 10 '10 at 21:41
...
Why is isNaN(null) == false in JS?
...s question, but semantically it's referring specifically to the value NaN. From Wikipedia for NaN:
NaN (Not a Number) is a value of the numeric data type representing an undefined or unrepresentable value, especially in floating-point calculations.
In most cases we think the answer to "is nul...
What's the difference between integer class and numeric class in R
...s are whole numbers. For example, 1:5 creates an integer vector of numbers from 1 to 5. You don't need to append the letter L.
> class(1:5)
[1] "integer"
Reference: https://www.quora.com/What-is-the-difference-between-numeric-and-integer-in-R
...
Including a .js file within a .js file [duplicate]
...tionality to load, you can make the rest of your javascript file be called from the load event on that script tag.
This function is based on the functionality of jQuery $.getScript()
function loadScript(src, f) {
var head = document.getElementsByTagName("head")[0];
var script = document.creat...
Simple insecure two-way data “obfuscation”?
...rypted bytes to the stream,
* then read the encrypted result back from the stream.
*/
#region Write the decrypted value to the encryption stream
CryptoStream cs = new CryptoStream(memoryStream, EncryptorTransform, CryptoStreamMode.Write);
cs.Write(bytes, 0, ...
Dealing with float precision in Javascript [duplicate]
...
From this post: How to deal with floating point number precision in JavaScript?
You have a few options:
Use a special datatype for decimals, like decimal.js
Format your result to some fixed number of significant digits, li...