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How does one reorder columns in a data frame?
... has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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Syntax for creating a two-dimensional array
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@Nawaz No, Arrays are Object in java and memory is allocated to Objects only by using new keyword.
– roottraveller
Jun 13 '17 at 9:40
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Unable to start debugging because the object invoked has disconnected from its clients
...e control engine
Review the list of extensions and plugins. Try to disable all or some of them
Close Visual Studio and kill all the development processes: devenv, mspdbsrv, vcpkgsrv, msbuild, msvsmon, vshub, vstest etc
Remove .suo, .ncb, .VC.db, .VC.VC.opendb files of the solution as well as .vs dir...
Creating an R dataframe row-by-row
...ke to construct a dataframe row-by-row in R. I've done some searching, and all I came up with is the suggestion to create an empty list, keep a list index scalar, then each time add to the list a single-row dataframe and advance the list index by one. Finally, do.call(rbind,) on the list.
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Get number days in a specified month using JavaScript? [duplicate]
...t with 1 instead of 0 as is normal with Javascript dates, because it's actually switching to the previous month because the day number is 0.
– Allan Wintersieck
Jul 15 '16 at 15:16
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Why does 2 mod 4 = 2?
...oup of 6 people, and the remainder is 0 or no bananas left when you shared all 6 bananas on 6 people.
Now, for 7 bananas and 6 people in group, you then will have 7 mod 6 = 1, this because you gave 6 people 1 banana each, and 1 banana is the remainder.
For 12 mod 6 or 12 bananas shared on 6 peo...
Generating random number between 1 and 10 in Bash Shell Script [duplicate]
... because you can't divide that evenly into groups of 10, there is a very small bias against 9 and 10 in this implementation. Most people shouldn't need to worry about this, because you shouldn't be using $RANDOM for security purposes anyway.
– Brad Koch
Feb 13...
What difference does .AsNoTracking() make?
I have a question regarding the .AsNoTracking() extension, as this is all quite new and quite confusing.
6 Answers
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How can I remove the decimal part from JavaScript number?
... on how you wanted to remove the decimal.
Math.trunc() isn't supported on all platforms yet (namely IE), but you could easily use a polyfill in the meantime.
Another method of truncating the fractional portion with excellent platform support is by using a bitwise operator (.e.g |0). The side-effec...
How can I unstage my files again after making a local commit?
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What is described in this answer is actually what git commit --amend does; but with a much more complicated workflow. This does not answer the question OP asked, in spite of giving a good direction (git reset).
– 7heo.tk
May 1...