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Should I use a data.frame or a matrix?
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Part of the answer is contained already in your question: You use data frames if columns (variables) can be expected to be of different types (numeric/character/logical etc.). Matrices are for data of the same type.
Consequently, the choice matrix/data.frame ...
Why can't yield return appear inside a try block with a catch?
...his restriction is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant.
There are a few things like this that I've already encountered:
Attributes not being able to be generic
Inability for X to derive from X.Y (a nested class in X)
I...
How can I use interface as a C# generic type constraint?
... Marc Gravell♦Marc Gravell
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My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())
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vll
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answered Sep 15 '09 at 0:24
Brian R. BondyBrian R. Bondy
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How is Perl's @INC constructed? (aka What are all the ways of affecting where Perl modules are searc
...env -i perl -V
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@INC:
/usr/lib/perl5/site_perl/5.18.0/x86_64-linux-thread-multi-ld
/usr/lib/perl5/site_perl/5.18.0
/usr/lib/perl5/5.18.0/x86_64-linux-thread-multi-ld
/usr/lib/perl5/5.18.0
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Note . at the end; this is the current directory (which is not necessarily the same as the script'...
Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
...an array of type Integer[]. For reasons which should be obvious, this is bad news. Java's type system actually allows this at compile time. The JVM will "helpfully" throw an ArrayStoreException at runtime. Scala's type system prevents this problem because the type parameter on the Array class is...
Difference between Repository and Service Layer?
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Repository Layer gives you additional level of abstraction over data access. Instead of writing
var context = new DatabaseContext();
return CreateObjectQuery<Type>().Where(t => t.ID == param).First();
to get a single item from database, you...
What should every developer know about databases? [closed]
... a database, and you weren't sharing data you were either involved in an academic project or you were wasting resources, including yourself. Setting up a database and taming a DBMS were such monumental tasks that the payback, in terms of data exploited multiple times, had to be huge to match the in...
Differences between ExpandoObject, DynamicObject and dynamic
...icMetaObjectProvider.
ExpandoObject is a simple class which allows you to add members to an instance and use them dynamically.
DynamicObject is a more advanced implementation which can be inherited to easily provide customized behavior.
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Java 8: performance of Streams vs Collections
I'm new to Java 8. I still don't know the API in depth, but I've made a small informal benchmark to compare the performance of the new Streams API vs the good old Collections.
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