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How to sum array of numbers in Ruby?
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Try this:
array.inject(0){|sum,x| sum + x }
See Ruby's Enumerable Documentation
(note: the 0 base case is needed so that 0 will be returned on an empty array instead of nil)
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Python dict how to create key or append an element to key?
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edited Sep 30 '14 at 22:31
answered Oct 16 '12 at 0:43
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How to check if a file exists in Documents folder?
...rchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0];
NSString* foofile = [documentsPath stringByAppendingPathComponent:@"foo.html"];
BOOL fileExists = [[NSFileManager defaultManager] fileExistsAtPath:foofile];
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SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
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Since 3.24.0 SQLite also supports upsert, so now you can simply write the following
INSERT INTO visits (ip, hits)
VALUES ('127.0.0.1', 1)
ON CONFLICT(ip) DO UPDATE SET hits = hits + 1;
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How to set a stroke-width:1 on only certain sides of SVG shapes?
...tangle.
rect { fill: none; stroke: black; }
.top { stroke-dasharray: 0,50,150 }
.left { stroke-dasharray: 150,50 }
.bottom { stroke-dasharray: 100,50 }
.right { stroke-dasharray: 50,50,100 }
<svg height="300">
<rect x="0.5" y="0.5" width="50" height="50" class="top"/>
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Format number to 2 decimal places
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You want to use the TRUNCATE command.
https://dev.mysql.com/doc/refman/8.0/en/mathematical-functions.html#function_truncate
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int value under 10 convert to string two digit number
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i.ToString("00")
or
i.ToString("000")
depending on what you want
Look at the MSDN article on custom numeric format strings for more options: http://msdn.microsoft.com/en-us/library/0c899ak8(VS.71).aspx
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Flatten an irregular list of lists
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390
Using generator functions can make your example a little easier to read and probably boost the p...
Python: using a recursive algorithm as a generator
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answered Oct 29 '08 at 23:53
Markus JarderotMarkus Jarderot
76.3k1717 gold badges126126 silver badges133133 bronze badges
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What is the default initialization of an array in Java?
...hing that holds an object) that is null.
For int/short/byte/long that is a 0.
For float/double that is a 0.0
For booleans that is a false.
For char that is the null character '\u0000' (whose decimal equivalent is 0).
When you create an array of something, all entries are also zeroed. So your arra...