[R] For loop...

[Bert Gunter]

But ...

On Sun, Nov 4, 2012 at 4:24 AM, Berend Hasselman <bhh at xs4all.nl> wrote:
>
> On 04-11-2012, at 13:07, SHAILLY MEHROTRA wrote:
>
>> Dear R-users,
>>
>> I have dataset  with column A and B with1000 values,
>>
>> For each of column C value (C = seq(1,1000,1), I want to repeat A and B
>> values and calculate R = A+B*C for each row.
>>
>> I want to get output as
>>
>> A              B            C         R
>> 1              10           1         11
>> 2              30           1         32
>> 3              50           1         53
>> 1000       1000        1        2000
>> 1              10           2        21
>> 2               30          2        62
>> 3               50          2        103
>> 1000        1000       2        3000
>>
>> How can I do it using for loop?
>>
>
> You don't do that with a for loop.
> You can do it like this, assuming your dataset is a data.frame and is named "dat"
>
>
> dat["R"] <- dat["A"] + dat["B"]*dat["C"]

dat[["R"]] <- dat[["A"]] + dat[["B"]]*dat[["C"]]

would be better, I believe.

And the OP would be well-advised to read the Intro to R tutorial
before posting further on this list.

To quote Rolf Turner on this list:

" Learn something about R; don't just hammer and hope.  Read the
introductory manuals and scan the FAQ.."

-- Bert

>
> dat[,"R"] <- dat[,"A"] + dat[,"B"]*dat[,"C"]
>
> Read the R intro manual.
>
> Berend
>
>> Thanks
>> Shailly
>>
>>       [[alternative HTML version deleted]]
>>
>> ______________________________________________
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>> https://stat.ethz.ch/mailman/listinfo/r-help
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>> and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.



-- 

Bert Gunter
Genentech Nonclinical Biostatistics

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