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How do I delete rows in a data frame?
... 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" myData if you wanted to drop those row...
The name 'ConfigurationManager' does not exist in the current context
I am trying to access connectionStrings from the config file. The code is ASP.NET + C#. I have added System.Configuration to reference and also mentioned with using. But still it wouldn't accept the assembly.
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Visual Studio Solutions Folder as real Folders
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No special setting. I don't think it's supported.
You can create real folders in a "project" within the solution, but not in the solution itself.
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Choosing Java vs Python on Google App Engine
Currently Google App Engine supports both Python & Java. Java support is less mature. However, Java seems to have a longer list of libraries and especially support for Java bytecode regardless of the languages used to write that code. Which language will give better performance and more power? Pleas...
What is Scala's yield?
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It is used in sequence comprehensions (like Python's list-comprehensions and generators, where you may use yield too).
It is applied in combination with for and writes a new element into the resulting sequence.
Simple example (from sc...
What are the best practices for using Assembly Attributes?
I have a solution with multiple project. I am trying to optimize AssemblyInfo.cs files by linking one solution wide assembly info file. What are the best practices for doing this? Which attributes should be in solution wide file and which are project/assembly specific?
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Relationship between hashCode and equals method in Java [duplicate]
I read in many places saying while override equals method in Java, should override hashCode method too, otherwise it is "violating the contract".
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How to get the path of the batch script in Windows?
I know that %0 contains the full path of the batch script, e.g. c:\path\to\my\file\abc.bat
7 Answers
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Difference between ref and out parameters in .NET [duplicate]
What is the difference between ref and out parameters in .NET? What are the situations where one can be more useful than the other? What would be a code snippet where one can be used and another can't?
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Anyone else find naming classes and methods one of the most difficult parts in programming? [closed]
So I'm working on this class that's supposed to request help documentation from a vendor through a web service. I try to name it DocumentRetriever , VendorDocRequester , DocGetter , but they just don't sound right. I ended up browsing through dictionary.com for half an hour trying to come up wi...