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How can you determine a point is between two other points on a line segment?
Let's say you have a two dimensional plane with 2 points (called a and b) on it represented by an x integer and a y integer for each point.
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SQL query return data from multiple tables
...1 - Joins and Unions
This answer covers:
Part 1
Joining two or more tables using an inner join (See the wikipedia entry for additional info)
How to use a union query
Left and Right Outer Joins (this stackOverflow answer is excellent to describe types of joins)
Intersect queries (and how to repr...
Python assigning multiple variables to same value? list behavior
I tried to use multiple assignment as show below to initialize variables, but I got confused by the behavior, I expect to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
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TypeError: got multiple values for argument
...d the other threads that had to do with this error and it seems that my problem has an interesting distinct difference than all the posts I read so far, namely, all the other posts so far have the error in regards to either a user created class or a builtin system resource. I am experiencing this pr...
Why is XOR the default way to combine hashes?
Say you have two hashes H(A) and H(B) and you want to combine them. I've read that a good way to combine two hashes is to XOR them, e.g. XOR( H(A), H(B) ) .
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PHP Sort Array By SubArray Value
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Use usort.
function cmp_by_optionNumber($a, $b) {
return $a["optionNumber"] - $b["optionNumber"];
}
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usort($array, "cmp_by_optionNumber");
In PHP ≥5.3, you should use an anonymous function instead:
usort($array, function ($a, $b) {
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How to merge two sorted arrays into a sorted array? [closed]
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A minor improvement, but after the main loop, you could use System.arraycopy to copy the tail of either input array when you get to the end of the other. That won't change the O(n) performance characteristics of your solution, though.
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SQL update fields of one table from fields of another one
I have two tables:
7 Answers
7
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Access multiple elements of list knowing their index
...r.itemgetter:
from operator import itemgetter
a = [-2, 1, 5, 3, 8, 5, 6]
b = [1, 2, 5]
print(itemgetter(*b)(a))
# Result:
(1, 5, 5)
Or you can use numpy:
import numpy as np
a = np.array([-2, 1, 5, 3, 8, 5, 6])
b = [1, 2, 5]
print(list(a[b]))
# Result:
[1, 5, 5]
But really, your current solu...
Center a map in d3 given a geoJSON object
Currently in d3 if you have a geoJSON object that you are going to draw you have to scale it and translate it in order to get it to the size that one wants and translate it in order to center it. This is a very tedious task of trial and error, and I was wondering if anyone knew a better way to obtai...