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Sample random rows in dataframe
...ruggling to find the appropriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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Listing all permutations of a string/integer
...f interviews though) is to take a string or an integer and list every possible permutation.
28 Answers
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Return anonymous type results?
Using the simple example below, what is the best way to return results from multiple tables using Linq to SQL?
16 Answers
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Fast way of counting non-zero bits in positive integer
I need a fast way to count the number of bits in an integer in python.
My current solution is
9 Answers
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SQL JOIN vs IN performance?
...g a JOIN or an IN will give me the correct results... Which typically has better performance and why? How much does it depend on what database server you are running? (FYI I am using MSSQL)
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Simultaneously merge multiple data.frames in a list
...o merge. The issue here is that each data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, I could merely rbind , for which plyr's rbind...
Learning about LINQ [closed]
One of the things I've asked a lot about on this site is LINQ . The questions I've asked have been wide and varied and often don't have much context behind them. So in an attempt to consolidate the knowledge I've acquired on Linq I'm posting this question with a view to maintaining and updating it ...
git rebase, keeping track of 'local' and 'remote'
When doing a git rebase, I often have difficulty working out what is happening with the 'local' and 'remote' when resolving conflicts. I sometimes have the impression that they swap sides from one commit to the next.
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Math - mapping numbers
How do I map numbers, linearly, between a and b to go between c and d.
9 Answers
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创建自定义 TinyWebDB 服务 · App Inventor 2 中文网
...nyWebDB can be used to facilitate communication between phones and apps (e.g., multi-player games).
By default, the TinyWebDB component stores data on a test service provided by App Inventor, http://tinywebdb.appinventor.mit.edu/ . This service is helpful for testing, but it is shared by all App In...