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What’s the difference between “Array()” and “[]” while declaring a JavaScript array?
...hese are the same
b = new Array(), // a and b are arrays with length 0
c = ['foo', 'bar'], // these are the same
d = new Array('foo', 'bar'), // c and d are arrays with 2 strings
// these are different:
e = [3] // e.length == 1, e[0] == 3
f = new Ar...
JavaScript checking for null vs. undefined and difference between == and ===
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+50
How do I check a variable if it's null or undefined...
Is the variable null:
if (a === null)
// or
if (a == null) // but see not...
Convert between UIImage and Base64 string
...ta format
let imageData:NSData = NSData.init(contentsOfURL: url)!
Swift 2.0 > Encoding
let strBase64:String = imageData.base64EncodedStringWithOptions(.Encoding64CharacterLineLength)
Swift 2.0 > Decoding
let dataDecoded:NSData = NSData(base64EncodedString: strBase64, options: NSDataBase64Dec...
Elastic search, multiple indexes vs one index and types for different data sets?
...
190
There are different implications to both approaches.
Assuming you are using Elasticsearch's de...
CHECK constraint in MySQL is not working
...
MySQL 8.0.16 is the first version that supports CHECK constraints.
Read https://dev.mysql.com/doc/refman/8.0/en/create-table-check-constraints.html
If you use MySQL 8.0.15 or earlier, the MySQL Reference Manual says:
The CHECK...
How to access property of anonymous type in C#?
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answered Jul 29 '09 at 22:50
Greg BeechGreg Beech
119k3939 gold badges198198 silver badges238238 bronze badges
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Loop backwards using indices in Python?
I am trying to loop from 100 to 0. How do I do this in Python?
15 Answers
15
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How to get a variable value if variable name is stored as string?
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answered Dec 17 '09 at 12:09
Phil RossPhil Ross
22.5k99 gold badges6666 silver badges7474 bronze badges
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Numpy array dimensions
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answered Jun 17 '10 at 12:59
Felix KlingFelix Kling
666k151151 gold badges968968 silver badges10321032 bronze badges
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Lock, mutex, semaphore… what's the difference?
...|
edited Jan 29 '19 at 7:40
answered Feb 25 '10 at 9:21
Pet...