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Repeat each row of data.frame the number of times specified in a column
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Here's one solution:
df.expanded <- df[rep(row.names(df), df$freq), 1:2]
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
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Does anyone still use [goto] in C# and if so why? [closed]
I was wondering whether anyone still uses the "goto" keyword syntax in C# and what possible reasons there are for doing so.
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Attempted to read or write protected memory. This is often an indication that other memory is corrup
I'm hoping someone can enlighten me as to what could possibly be causing this error:
26 Answers
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What is the difference between & and && in Java?
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What's the reason to write one & or | in if statement? It never will be faster than && and ||. Why do we want to check second condition if we already can have answer? Can you provide and realistic example, please?
– Mi...
How to use/install gcc on Mac OS X 10.8 / Xcode 4.4
... menu > Preferences > Downloads.
Alternatively, there are stand-alone installation packages both for Mountain Lion (10.8) and for Mavericks (10.9).
This package enables UNIX-style development via Terminal by installing
command line developer tools, as well as Mac OS X SDK frameworks a...
Generate list of all possible permutations of a string
...tely isn't the best way to generate these, but it's an interesting aside, none-the-less.
Knuth (volume 4, fascicle 2, 7.2.1.3) tells us that (s,t)-combination is equivalent to s+1 things taken t at a time with repetition -- an (s,t)-combination is notation used by Knuth that is equal to . We can fi...
Replace duplicate spaces with a single space in T-SQL
I need to ensure that a given field does not have more than one space (I am not concerned about all white space, just space) between characters.
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How to pass a variable from Activity to Fragment, and pass it back?
... I am still confused on what method is the best to use, yours, or the one below answered by @Elenasys
– Yoann Hercouet
Apr 18 '16 at 12:46
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How to recursively download a folder via FTP on Linux [closed]
...ectory where you launch wget. The number 5 is used to filter out the 5 components of the path. The double slash means an extra component.
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JavaScript moving element in the DOM
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Yes, but who only does this one thing?
– tvanfosson
Sep 1 '09 at 18:29
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