[R] rowsum

[jim holtman]

Another option to consider:

> x
    A   B   C
1  89   1 140
2  89   6  20
3  89  29 137
4  89  52  13
5  89  57  10
6  89  97  23
7  89   1  37
8  89   1  12
9  89   1   3
10 52   1  11
11 52   1  31
12 52   1  16
13 52   1   6
14 52   1  10
15 52   1  13
16 52   1  10
17 52   1  25
18 52   1   2
19 52  59  38
20 52  97  75
21 57   1  14
22 57   1  13
23 57   1  14
24 57 114  12
25 57   1  23
26 57   6  26
> require(sqldf)
> sqldf("select A, B, sum(C) from x group by A, B")
    A   B sum(C)
1  52   1    124
2  52  59     38
3  52  97     75
4  57   1     64
5  57   6     26
6  57 114     12
7  89   1    192
8  89   6     20
9  89  29    137
10 89  52     13
11 89  57     10
12 89  97     23
>


On Wed, Oct 20, 2010 at 5:42 AM, xtracto <b2017700 at lhsdv.com> wrote:
>
> Hello,
>
> I am trying to achieve something which I *think* is possible using rowsum,
> but a little help should be useful:
>
> Consider the following dataframe DF0:
> A       B       C
> 89      1       140
> 89      06      20
> 89      29      137
> 89      52      13
> 89      57      10
> 89      97      23
> 89      1       37
> 89      1       12
> 89      1       3
> 52      1       11
> 52      1       31
> 52      1       16
> 52      1       6
> 52      1       10
> 52      1       13
> 52      1       10
> 52      1       25
> 52      1       2
> 52      59      38
> 52      97      75
> 57      1       14
> 57      1       13
> 57      1       14
> 57      114     12
> 57      1       23
> 57      06      26
>
>
> I need create a new dataframe containing the sums of all the rows where B =
> 1 for the different values of A, keeping the rows with other B values the
> same. That is, for this data sample, the result I expect is something like
> this (the order of the rows does not matter):
>
> A       B       C
> 89      1       192    #From adding up: [140 + 37 + 12 + 3]
> 89      06      20
> 89      29      137
> 89      52      13
> 89      57      10
> 89      97      23
> 52      1       124    # From adding up: [11 + 31 + 16 + 6 + 10 + 13 + 10 + 25 + 2]
> 52      59      38
> 52      97      75
> 57      1       64     #From adding up: [14 +13 +14 +23]
> 57      114     12
> 57      06      26
>
>
> Now, I now it should be possible to first separate the data in two sets,
> where
> DF1 <- DF0[DF0$B != 1,]
> DF2 <- DF0[DF0$B == 1,]
>
> Then I should apply sumrow to DF2 with some "group" vector, but I do not
> know where to go from here.
>
> Can anyone help?
> Thanks in advance!
>
>
> --
> View this message in context: http://r.789695.n4.nabble.com/rowsum-tp3003551p3003551.html
> Sent from the R help mailing list archive at Nabble.com.
>
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> and provide commented, minimal, self-contained, reproducible code.
>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?