[R] If() values in one dataframe then return values from another

David Winsemius dwinsemius at comcast.net
Mon Feb 4 19:08:55 CET 2013


On Feb 4, 2013, at 9:48 AM, Steven Ranney wrote:

> I have a large data frame ("data1") that looks like:
> 
>        A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A20
>   [1,]  0  0  0  0  0  0  0  0  0   0   0   0   0   1   0   0   0   0   0   0
>   [2,]  0  0  0  0  0  1  0  0  1   0   1   0   0   1   0   0   0   0   0   0
>   [3,]  1  1  0  1  1  1  1  1  1   1   1   0   1   1   0   0   0   0   0   0
>   [4,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   0   1   0   0   2
>   [5,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   0   1   2   0   2
>   [6,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   0   1   2   2   2
>   [7,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>   [8,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>   [9,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [10,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [11,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [12,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [13,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [14,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [15,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [16,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   2   2   2   2
>  [17,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   2   2   2   2   2
>  [18,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   2   2   2   2   2
>  [19,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   2   1   2   2   2
>  [20,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [21,]  0  0  0  0  0  0  0  0  0   0   0   0   0   0   0   0   0   0   0   0
>  [22,]  0  0  0  2  0  0  0  0  0   0   0   2   0   0   0   1   0   0   0   0
>  [23,]  0  0  0  2  0  0  0  1  0   0   0   2   0   0   0   2   0   0   0   2
>  [24,]  0  0  1  2  0  0  0  2  0   0   1   1   0   1   0   1   0   0   2   2
>  [25,]  0  1  1  2  0  2  2  2  1   1   1   1   0   1   1   1   1   0   2   2
>  [26,]  1  1  1  1  1  2  2  2  1   1   1   1   2   1   1   1   1   2   2   2
>  [27,]  1  1  1  1  1  2  1  2  1   1   1   1   2   1   1   1   1   2   2   2
>  [28,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [29,]  1  1  1  1  1  1  1  2  1   1   1   1   1   1   2   1   1   2   2   2
>  [30,]  1  1  1  2  1  1  1  2  1   1   1   1   1   1   1   2   1   2   2   2
>  [31,]  1  1  2  1  1  1  1  1  1   1   1   1   2   2   1   1   1   2   2   2
>  [32,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [33,]  1  1  1  1  1  3  3  3  3   1   3   3   1   1   2   1   1   2   2   2
>  [34,]  1  1  1  1  1  1  2  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [35,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   2   2   2   2
>  [36,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [37,]  1  1  1  1  1  1  1  1  1   1   1   1   1   1   1   1   1   2   2   2
>  [38,]  0  0  0  0  0  0  0  0  0   2   0   0   0   0   0   0   0   0   0   0
>  [39,]  0  0  0  0  0  0  0  0  0   2   0   0   2   0   0   2   0   0   0   2
>  [40,]  1  1  2  1  1  2  1  2  2   2   2   2   2   1   1   1   1   2   3   2
> 
> (data1 is actually 1,080 rows long.)
> 
> If there is a "3" in any row above, I'd like to be given the values
> from a second data frame ("meter"):
> 
>     meter
> 1                     20
> 2                     19
> 3                     18
> 4                     17
> 5                     16
> 6                     15
> 7                     14
> 8                     13
> 9                     12
> 10                    11
> 11                    10
> 12                     9
> 13                     8
> 14                     7
> 15                     6
> 16                     5
> 17                     4
> 18                     3
> 19                     2
> 20                     1
> 21                    20
> 22                    19
> 23                    18
> 24                    17
> 25                    16
> 26                    15
> 27                    14
> 28                    13
> 29                     8
> 30                     7
> 31                     6
> 32                     2
> 33                     1
> 34                    10
> 35                     4
> 36                     3
> 37                     2
> 38                    18
> 39                    17
> 40                    15
> 
> (meter is actually 1,080 rows long)

One hopes for the success of htis effort that 'data1' has an equal number of rows.

> 
> If there is no "3" row i of data1, I'd like to R to return "NA".
> 
> I've tried
> 
> for(i in 1:40){
> if( 
> }
> 

Generally sequential testing is best handled with `ifelse` rather than with for loops and `if () {} else{}`

mA <- ifelse ( apply(data, 1,  any),  meter, NA)


> But I'm given:
> 
>> mA
> [1] 15
> Levels: 1 10 11 12 13 14 15 16 17 18 19 2 20 3 4 5 6 7 8 9

The fact that you have constructed a factor variable suggest that you made an error in building the 'meter' data and that is it no numeric at the moment. The fact that it is only length = 1 is due to your not indexing the construction of 'mA' in your loop.


> 
> Can anyone give me some additional ideas to try?
> 
> Thanks -
> 

David Winsemius
Alameda, CA, USA



More information about the R-help mailing list