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What is the difference between “instantiated” and “initialized”?

...in C# are in 1 of 2 groups. Value types or Reference types. Types like int and DateTime are value types. In contrast, any class you create is a reference type. C# strings are also a reference type. Most things in the .NET framework are reference types. Parts of a Variable There is the variable nam...
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Generic method multiple (OR) type constraint

...t types. That means you could just as well leave out the generic parameter and provide overloads. – Botz3000 May 31 '12 at 13:00 ...
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The application may be doing too much work on its main thread

I am new to Android SDK/API environment. It's the first I am trying to draw a plot/chart. I tried running different kinds of sample codes the emulator using 3 different free libraries, nothing is showing in the layout screen. The logcat is repeating the following message: ...
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Which characters are valid in CSS class names/selectors?

...racter is a hyphen, the second character must2 be a letter or underscore, and the name must be at least 2 characters long. -?[_a-zA-Z]+[_a-zA-Z0-9-]* In short, the previous rule translates to the following, extracted from the W3C spec.: In CSS, identifiers (including element names, classes, ...
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How to randomize (or permute) a dataframe rowwise and columnwise?

...,] > df2 a b c 3 0 1 0 4 0 0 0 2 1 0 0 1 1 1 0 By default sample() randomly reorders the elements passed as the first argument. This means that the default size is the size of the passed array. Passing parameter replace=FALSE (the default) to sample(...) ensures that sampling is done withou...
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What is a “surrogate pair” in Java?

...mething about surrogate pairs . What is a surrogate pair in this context? And what are low and high surrogates? 7 An...
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How to tell if a string is not defined in a Bash shell script

...Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend using separate simple tests combined with &&. I've not encountered a system where there is a problem; that doesn't mean they didn't used to exist (but they are probably extremely rare these days, eve...
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Does MS SQL Server's “between” include the range boundaries?

...t_expression is greater than or equal to the value of begin_expression and less than or equal to the value of end_expression. DateTime Caveat NB: With DateTimes you have to be careful; if only a date is given the value is taken as of midnight on that day; to avoid missing times within your ...
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What does the “yield” keyword do?

What is the use of the yield keyword in Python, and what does it do? 42 Answers 42 ...
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SQL how to increase or decrease one for a int column in one command

... there a way to do this in one action or we have to get the existing value and then add or minus one on top of it? 6 Answer...