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Why does the indexing start with zero in 'C'?
...f the array is exactly contained in the memory location that array refers (0 elements away), so it should be denoted as array[0].
For more info:
http://developeronline.blogspot.com/2008/04/why-array-index-should-start-from-0.html
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What do the different readystates in XMLHttpRequest mean, and how can I use them?
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The full list of readyState values is:
State Description
0 The request is not initialized
1 The request has been set up
2 The request has been sent
3 The request is in process
4 The request is complete
(from https://www.w3schools.com/js/js_ajax_http_respo...
php is null or empty?
...LL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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RegEx - Match Numbers of Variable Length
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{[0-9]+:[0-9]+}
try adding plus(es)
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Pandas dataframe get first row of each group
...column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 ...
Is there an equivalent to e.PageX position for 'touchstart' event as there is for click event?
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180
Kinda late, but you need to access the original event, not the jQuery massaged one. Also, since...
Why does one hot encoding improve machine learning performance?
...h" and "US". Assume, without loss of generality, that these are encoded as 0, 1 and 2. You then have a weight w for this feature in a linear classifier, which will make some kind of decision based on the constraint w×x + b > 0, or equivalently w×x < b.
The problem now is that the weight w c...
Check if UIColor is dark or bright?
...o use is ((Red value * 299) + (Green value * 587) + (Blue value * 114)) / 1000.
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Creating a comma separated list from IList or IEnumerable
...ng"};
string joined = string.Join(",", strings);
Detail & Pre .Net 4.0 Solutions
IEnumerable<string> can be converted into a string array very easily with LINQ (.NET 3.5):
IEnumerable<string> strings = ...;
string[] array = strings.ToArray();
It's easy enough to write the equiv...