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Find nearest latitude/longitude with an SQL query
...
showClosest.php
<?PHP
/**
* Use the Haversine Formula to display the 100 closest matches to $origLat, $origLon
* Only search the MySQL table $tableName for matches within a 10 mile ($dist) radius.
*/
include("./assets/db/db.php"); // Include database connection function
$db = new database();...
Is there a use-case for singletons with database access in PHP?
...nswered Nov 1 '12 at 18:34
unity100unity100
77088 silver badges1616 bronze badges
...
What is an example of the Liskov Substitution Principle?
...ariant:
void invariant(Rectangle r) {
r.setHeight(200)
r.setWidth(100)
assert(r.getHeight() == 200 and r.getWidth() == 100)
}
However, this invariant must be violated by a correct implementation of Square, therefore it is not a valid substitute of Rectangle.
...
How to create a drop shadow only on one side of an element?
...
.box-shadow:after {
content:"";
position:absolute;
width:100%;
bottom:1px;
z-index:-1;
transform:scale(.9);
box-shadow: 0px 0px 8px 2px #000000;
}
<div id="box" class="box-shadow"></div>
UPDATE 3
All my previous answers have been using extr...
How do I force Postgres to use a particular index?
...st perform a sequence / primary key scan instead. Conclusion - there is no 100% reliable method to force some index usage for PostgreSql server.
– Agnius Vasiliauskas
May 17 '18 at 6:42
...
SortedList, SortedDictionary and Dictionary
...4. Anything beyond will see your 2:1 ratio quickly go up. For example if n=100 then you should have O(log n) = 15. Following a similiar thinking, your O(1) would weight 100. Conclusion: O(n) looses the battle fairly quickly. If it does not, it means your array is small, and then efficiency is not a ...
Optimal number of threads per core
...sting that the quad core system seems to not at higher thread numbers (<100 anyway) the way the others do.
– Jim Garrison
Sep 28 '12 at 16:30
48
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Are Swift variables atomic?
...
Details
Xcode 9.1, Swift 4
Xcode 10.2.1 (10E1001), Swift 5
Links
apple.developer.com Dispatch
Grand Central Dispatch (GCD) and
Dispatch Queues in Swift 3
Creating Thread-Safe Arrays in
Swift
Mutexes and closure capture in Swift
Implemented types
AtomicArray
At...
How to compare two colors for similarity/difference
...difference in percentage.
(pctDiffRed + pctDiffGreen + pctDiffBlue) / 3 * 100
Which would give you a difference in percentage between c1 and c2.
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How to add a new row to an empty numpy array
...g the loop:
In [210]: %%timeit
.....: l = []
.....: for i in xrange(1000):
.....: l.append([3*i+1,3*i+2,3*i+3])
.....: l = np.asarray(l)
.....:
1000 loops, best of 3: 1.18 ms per loop
In [211]: %%timeit
.....: a = np.empty((0,3), int)
.....: for i in xrange(1000):
.......