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Filtering a data frame by values in a column [duplicate]
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The subset command is not necessary. Just use data frame indexing
studentdata[studentdata$Drink == 'water',]
Read the warning from ?subset
This is a convenience function intended for use interactively. For
programming it is bette...
Correct use of transactions in SQL Server
I have 2 commands and need both of them executed correctly or none of them executed. So I think I need a transaction, but I don't know how to use it correctly.
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Augmented Reality SDK with OpenCV [closed]
...d tutorials on the topic, which steps to follow, possible algorithms, fast and efficient coding for real-time performance etc.
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How to ALTER multiple columns at once in SQL Server
...e., so, whats the big deal, just use multiple ALTER TABLE ALTER COLUMN commands?
– KM.
Aug 12 '10 at 12:56
7
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Getting current device language in iOS?
...n of the device - not the currently selected language. These are often one and the same. However, if I am in North America and I set my language to Japanese, my region will still be English (United States). In order to retrieve the currently selected language, you can do:
NSString * language = [[NS...
Having issue with multiple controllers of the same name in my project
...at the 4th parameter here can be a bit confusing because of type inference and variable meaning. The 4th parameter can be a string array to constrain by namespace, an object to add IRouteConstraints OR strings that can be interpreted as constraints, or you can have 5 parameters and include both. asp...
Nested Git repositories?
... As a relative git beginner, I found this blog/tutorial easier to understand chrisjean.com/2009/04/20/… It takes a simpler approach by focusing on just git instead of having the context of a helper shell script; I found it easier to read.
– John K
May 16 '1...
Performance of Find() vs. FirstOrDefault() [duplicate]
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I was able to mimic your results so I decompiled your program and there is a difference between Find and FirstOrDefault.
First off here is the decompiled program. I made your data object an anonmyous data item just for compilation
List<\u003C\u003Ef__AnonymousType0<string>...
What is the use of GO in SQL Server Management Studio & Transact SQL?
SQL Server Management Studio always inserts a GO command when I create a query using the right click "Script As" menu. Why? What does GO actually do?
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How do I remove an array item in TypeScript?
I have an array that I've created in TypeScript and it has a property that I use as a key. If I have that key, how can I remove an item from it?
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