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Two-dimensional array in Swift
...Int]] = []
OR if you need an array of predefined size (as mentioned by @0x7fffffff in comments):
// 2 dimensional array of arrays of Ints set to 0. Arrays size is 10x5
var arr = Array(count: 3, repeatedValue: Array(count: 2, repeatedValue: 0))
// ...and for Swift 3+:
var arr = Array(repeating: ...
What is Weak Head Normal Form?
...
404
I'll try to give an explanation in simple terms. As others have pointed out, head normal form d...
Why does parseInt(1/0, 19) return 18?
...
The result of 1/0 is Infinity.
parseInt treats its first argument as a string which means first of all Infinity.toString() is called, producing the string "Infinity". So it works the same as if you asked it to convert "Infinity" in base 19 ...
How to count the number of true elements in a NumPy bool array
...xample:
>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is ...
How can I sort arrays and data in PHP?
...te a comparison function. That function takes two elements and must return 0 if these elements are considered equal, a value lower than 0 if the first value is lower and a value higher than 0 if the first value is higher. That's all that's needed:
function cmp(array $a, array $b) {
if ($a['foo']...
Double vs. BigDecimal?
...s a certain precision. Working with doubles of various magnitudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and ...
How do write IF ELSE statement in a MySQL query
...
150
You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case when...
How do you make an array of structs in C?
...
107
#include<stdio.h>
#define n 3
struct body
{
double p[3];//position
double v[3];//...
A weighted version of random.choice
...
Since version 1.7.0, NumPy has a choice function that supports probability distributions.
from numpy.random import choice
draw = choice(list_of_candidates, number_of_items_to_pick,
p=probability_distribution)
Note that probabi...
How to initialize an array's length in JavaScript?
..., e.g.
var data = [];
var length = 5; // user defined length
for(var i = 0; i < length; i++) {
data.push(createSomeObject());
}
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