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How can I generate random alphanumeric strings?

...retty much linearly when generating longer strings (so long as there's actually enough memory available). Having said that, Dan Rigby's answer was almost twice as fast as this one in every test. – LukeH Aug 28 '09 at 0:33 ...
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What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]

...tf8_unicode_ci uses the standard Unicode Collation Algorithm, supports so called expansions and ligatures, for example: German letter ß (U+00DF LETTER SHARP S) is sorted near "ss" Letter Œ (U+0152 LATIN CAPITAL LIGATURE OE) is sorted near "OE". utf8_general_ci does not support expansions/liga...
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What's the difference between parenthesis $() and curly bracket ${} syntax in Makefile?

... like unomadh GNU make example. From the GNU make manual on the Function Call Syntax (emphasis mine): […] If the arguments themselves contain other function calls or variable references, it is wisest to use the same kind of delimiters for all the references; write $(subst a,b,$(x)), not $(sub...
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insert multiple rows via a php array into mysql

...like you might be running into string-handling problems in PHP, which is really an algorithm problem, not a language one. Basically, when working with large strings, you want to minimize unnecessary copying. Primarily, this means you want to avoid concatenation. The fastest and most memory efficient...
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How can I access an internal class from an external assembly?

...people who publish things as internals which are really part of the public API? Or they used InternalsVisibleTo but didn’t include your assembly? If the symbol isn’t truly hidden, it’s part of the ABI. – binki Oct 4 '17 at 23:05 ...
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What is process.env.PORT in Node.js?

...t may independently configure the process.env.PORT variable for you; after all, your script runs in their environment. Amazon's Elastic Beanstalk does this. If you try to set a static port value like 3000 instead of process.env.PORT || 3000 where 3000 is your static setting, then your application w...
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How does inheritance work for Attributes?

...AttributeUsage (Inherited = True)] MyUberAttribute : Attribute { string _SpecialName; public string SpecialName { get { return _SpecialName; } set { _SpecialName = value; } } } Then use the Attribute by decorating a super-class... [MyUberAttribute(SpecialName = "Bob")] clas...
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Copy constructor versus Clone()

...r specified whether the Clone() method on ICloneable should be a deep or shallow clone, thus the interface is semantically broken as your callers won't know whether the call will deep or shallow clone the object. Instead, you should define your own IDeepCloneable (and IShallowCloneable) interfaces ...
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Find integer index of rows with NaN in pandas dataframe

... And just in case, if you want to find the coordinates of 'nan' for all the columns instead (supposing they are all numericals), here you go: df = pd.DataFrame([[0,1,3,4,np.nan,2],[3,5,6,np.nan,3,3]]) df 0 1 2 3 4 5 0 0 1 3 4.0 NaN 2 1 3 5 6 NaN 3.0 3 np.where(np.as...
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Using comparison operators in Scala's pattern matching system

...t; println("less than ten") } Edit: Note that this is more than superficially different to putting an if after the =>, because a pattern won't match if the guard is not true. share | improve th...