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“var” or no “var” in JavaScript's “for-in” loop?
...ave more than one for-loop in one scope? You will either have to reuse the index (no var), or you will have to declare lots and lots of new variables (j, k, l, m, …) which you will never use again.
– armin
Sep 2 '15 at 5:14
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How to select date from datetime column?
...
The first one is very slow and ignores the indexes. It is better to have LIKE 'date%'
– kachar
Feb 22 '13 at 10:03
...
Find nearest value in numpy array
...ray,value):
'''Given an ``array`` , and given a ``value`` , returns an index j such that ``value`` is between array[j]
and array[j+1]. ``array`` must be monotonic increasing. j=-1 or j=len(array) is returned
to indicate that ``value`` is out of range below and above respectively.'''
...
Serving static files with Sinatra
...ill serve assets in public. For the empty route, you'll want to render the index document.
require 'rubygems'
require 'sinatra'
get '/' do
File.read(File.join('public', 'index.html'))
end
Routes should return a String which become the HTTP response body. File.read opens a file, reads the file,...
Replace a character at a specific index in a string?
I'm trying to replace a character at a specific index in a string.
8 Answers
8
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Counting the occurrences / frequency of array elements
...haps a third-party for-loop, but I sort of ignored that since the standard index-based for-loops are sadly the default.
– ninjagecko
May 25 '11 at 18:51
2
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Contains case insensitive
... referrer. This method turns the string in a lower case string. Then, use .indexOf() using ral instead of Ral.
if (referrer.toLowerCase().indexOf("ral") === -1) {
The same can also be achieved using a Regular Expression (especially useful when you want to test against dynamic patterns):
if (!/R...
Accessing an array out of bounds gives no error, why?
...esson on arrays and their relationships with pointers:
When you use array indexing, you are really using a pointer in disguise (called a "reference"), that is automatically dereferenced. This is why instead of *(array[1]), array[1] automatically returns the value at that value.
When you have a poi...
Retrieve a Fragment from a ViewPager
...ow. If using FragmentStatePagerAdapter its worth looking at this. Grabbing indexes that are not the current one in a FragmentStateAdapter is not as useful as by the nature of it these will be completely torn down went out of view / out of offScreenLimit bounds.
THE UNHAPPY PATHS
Wrong: Maintain yo...
map function for objects (instead of arrays)
...t = { 'a': 1, 'b': 2, 'c': 3 };
Object.keys(myObject).map(function(key, index) {
myObject[key] *= 2;
});
console.log(myObject);
// => { 'a': 2, 'b': 4, 'c': 6 }
But you could easily iterate over an object using for ... in:
var myObject = { 'a': 1, 'b': 2, 'c': 3 };
for (...