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What is a “cache-friendly” code?
...ran,matlab) vs. row-major ordering (ex. c,c++) for storing two dimensional arrays. For example, consider the following matrix:
1 2
3 4
In row-major ordering, this is stored in memory as 1 2 3 4; in column-major ordering, this would be stored as 1 3 2 4. It is easy to see that implementations which ...
Get Insert Statement for existing row in MySQL
...me). Because Nigel Johnson pointed it out, I added NULL handling.
I used $array[$key] because I was worried it might somehow change, but unless something is horribly wrong, it shouldn't anyway.
<?php
function show_inserts($mysqli,$table, $where=null) {
$sql="SELECT * FROM `{$table}`".(is_nu...
Need a simple explanation of the inject method
...ns the accumulator, which in this case is the sum of all the values in the array, or 10.
Here's another simple example to create a hash from an array of objects, keyed by their string representation:
[1,"a",Object.new,:hi].inject({}) do |hash, item|
hash[item.to_s] = item
hash
end
In this ca...
How to check if element in groovy array/hash/collection/list?
How do I figure out if an array contains an element?
I thought there might be something like [1, 2, 3].includes(1) which would evaluate as true .
...
np.mean() vs np.average() in Python NumPy?
...tting correct results in some cases. I have a very large single-precision array that is accessed from an h5 file. If I take the mean along axes 0 and 1, I get wildly incorrect results unless I specify dtype='float64':
>T.shape
(4096, 4096, 720)
>T.dtype
dtype('<f4')
m1 = np.average(T, a...
Weird “[]” after Java method signature
...ns of the Java platform, a declaration form
for a method that returns an array is allowed to place (some or all of) the empty
bracket pairs that form the declaration of the array type after the parameter list.
This is supported by the obsolescent production:
MethodDeclarator:
...
TypeScript Objects as Dictionary types as in C#
... Map:
people.clear();
// Get Map size:
people.size;
// Extract keys into array (in insertion order):
let keys = Array.from(people.keys());
// Extract values into array (in insertion order):
let values = Array.from(people.values());
...
Return multiple values in JavaScript?
...
No, but you could return an array containing your values:
function getValues() {
return [getFirstValue(), getSecondValue()];
}
Then you can access them like so:
var values = getValues();
var first = values[0];
var second = values[1];
With the ...
Objective-C pass block as parameter
... // your code
}
Example
-(void) saveWithCompletionBlock: (void (^)(NSArray *elements, NSError *error))completionBlock{
// your code
}
Other use of cases:
2. Block as a Property
Template
@property (nonatomic, copy) returnType (^blockName)(parameters);
Example
@property (nonatomi...
Replacing a char at a given index in string? [duplicate]
... @Jason94, I'm not sure this is more efficient than using ToCharArray as in Jon's answer, you should run tests to see which one is faster.
– Thomas Levesque
Feb 20 '12 at 20:18
...