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How do I check that multiple keys are in a dict in a single pass?
...imer
>>> setup='''from random import randint as R;d=dict((str(R(0,1000000)),R(0,1000000)) for i in range(D));q=dict((str(R(0,1000000)),R(0,1000000)) for i in range(Q));print("looking for %s items in %s"%(len(q),len(d)))'''
>>> Timer('set(q) <= set(d)','D=1000000;Q=100;'+setup)....
How to extract the n-th elements from a list of tuples?
... than the list comprehension:
setup = 'elements = [(1,1,1) for _ in range(100000)];from operator import itemgetter'
method1 = '[x[1] for x in elements]'
method2 = 'map(itemgetter(1), elements)'
import timeit
t = timeit.Timer(method1, setup)
print('Method 1: ' + str(t.timeit(100)))
t = timeit.Timer...
Best data type to store money values in MySQL
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I prefer to use BIGINT, and store the values in by multiply with 100, so that it will become integer.
For e.g., to represent a currency value of 93.49, the value shall be stored as 9349, while displaying the value we can divide by 100 and display. This will occupy less storage space.
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Specifying Style and Weight for Google Fonts
...yle. Here's how the names map to CSS font weight numbers:
Thin 100
Extra Light 200
Light 300
Regular 400
Medium 500
Semi-Bold 600
Bold 700
Extra-Bold 800
Black 900
Note that very few fonts come in all 9 weights.
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Fastest way to find second (third…) highest/lowest value in vector or column
...chmarks below against most popular answers.
For 10 thousand numbers:
N = 10000
x = rnorm(N)
maxN <- function(x, N=2){
len <- length(x)
if(N>len){
warning('N greater than length(x). Setting N=length(x)')
N <- length(x)
}
sort(x,partial=len-N+1)[len-N+1]...
Truncate number to two decimal places without rounding
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GumboGumbo
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How does the Brainfuck Hello World actually work?
...
+100
1. Basics
To understand Brainfuck you must imagine infinite array of cells initialized by 0 each.
...[0][0][0][0][0]...
When bra...
Performance of Arrays vs. Lists
...Stopwatch watch = Stopwatch.StartNew();
for (int rpt = 0; rpt < 100; rpt++)
{
int len = list.Count;
for (int i = 0; i < len; i++)
{
chk += list[i];
}
}
watch.Stop();
Console.WriteLine("List/...
What is the memory consumption of an object in Java?
Is the memory space consumed by one object with 100 attributes the same as that of 100 objects, with one attribute each?
12...
What is the fastest way to create a checksum for large files in C#
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Don't checksum the entire file, create checksums every 100mb or so, so each file has a collection of checksums.
Then when comparing checksums, you can stop comparing after the first different checksum, getting out early, and saving you from processing the entire file.
It'll sti...