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Generate a random alphanumeric string in Cocoa
... *letters = @"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
-(NSString *) randomStringWithLength: (int) len {
NSMutableString *randomString = [NSMutableString stringWithCapacity: len];
for (int i=0; i<len; i++) {
[randomString appendFormat: @"%C", [letters c...
How to check if element exists using a lambda expression?
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Mark Hurd
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answered Apr 11 '14 at 6:24
MasudulMasudul
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Can I get chrome-devtools to actually search all JS sources?
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edited Oct 24 '19 at 21:29
Darryl Hein
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Error in SQL script: Only one statement is allowed per batch
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answered Sep 9 '13 at 13:02
Cosmin IonascuCosmin Ionascu
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How to check whether an object has certain method/property?
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Fraser
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answered Feb 25 '11 at 6:59
JulienJulien
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What is the way to quick-switch between tabs in Xcode 4
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297
Shortcuts are:
CMD + SHIFT + } - Select Next tab
CMD + SHIFT + { - Select Previous tab
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Replace all non-alphanumeric characters in a string
... any character that isn't a standard character or number such as (a-z or 0-9) with an asterisk. For example, "h^&ell`.,|o w]{+orld" is replaced with "h*ell*o*w*orld". Note that multiple characters such as "^&" get replaced with one asterisk. How would I go about doing this?
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Why are these numbers not equal?
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359
General (language agnostic) reason
Since not all numbers can be represented exactly in IEEE flo...
How to fix Error: listen EADDRINUSE while using nodejs?
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39 Answers
39
Active
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Float vs Decimal in ActiveRecord
...easure{ (1..10000000).each { |i| f * f } }
puts time_decimal
#=> 6.770960 seconds
puts time_float
#=> 0.988070 seconds
Answer
Use float when you don't care about precision too much. For example, some scientific simulations and calculations only need up to 3 or 4 significant digits. This...