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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
Where does Java's String constant pool live, the heap or the stack?
I know the concept of a constants pool and the String constant pool used by JVMs to handle String literals. But I don't know which type of memory is used by the JVM to store String constant literals. The stack or the heap? Since its a literal which is not associated with any instance I would assume ...
How do I convert an integer to binary in JavaScript?
...nswered Apr 22 '13 at 19:43
fernandosaviofernandosavio
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Why does integer overflow on x86 with GCC cause an infinite loop?
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When the standard says it's undefined behavior, it means it. Anything can happen. "Anything" includes "usually integers wrap around, but on occasion weird stuff happens".
Yes, on x86 CPUs, integers usually wrap the way you expect. This...
How do I pass multiple parameters into a function in PowerShell?
...g parameter, the first parameter seems to get all the data assigned to it, and remaining parameters are passed in as empty.
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What is the rationale for all comparisons returning false for IEEE754 NaN values?
...ify things a bit.
First off, floating-point numbers are not real numbers, and floating-point arithmetic does not satisfy the axioms of real arithmetic. Trichotomy is not the only property of real arithmetic that does not hold for floats, nor even the most important. For example:
Addition is not...
What is “android:allowBackup”?
...e, either open the lint warnings view, where you can select the lint error and see a longer explanation, or invoke the quick fix (Ctrl-1) on the error line, and one of the suggestions is "Explain this issue", which will also pop up a fuller explanation. If you are not using Eclipse, you can generate...
What is the use of the @ symbol in PHP?
... I had time to correct my suppress spelling after posting ... and damn you for enhancing with a link at the same time rages :P
– Aiden Bell
Jun 23 '09 at 12:12
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How do I properly compare strings in C?
...trying to get a program to let a user enter a word or character, store it, and then print it until the user types it again, exiting the program. My code looks like this:
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Can I simultaneously declare and assign a variable in VBA?
I'm new to VBA and want to know if I can convert the following declaration and assignment into one line:
5 Answers
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