[R] extraction of elements in a matrice???

[Gavin Simpson]

On Mon, 2009-08-10 at 14:13 +0000, Inchallah Yarab wrote:
> i have a matrice M and i want to extract only rows where GWP_Max is
> positif and smaller than 1000 but it is given me this:!!!???
> > M
>  Policy.Number GWP_Max
> 1 4001023 500
> 2 4001025 700
> 3 4001028 600
> 4 4001062 2335.1
> 5 6100001 2000
> 6 1060000006 1400
> 7 1060000009 77.19
> 8 1060000071 18898.88
> 9 1060000073 671.70015
> 10 1060000077 18898.88
> 11 1060000077 18898.88
> 12 1060000124 93541.87
> > M[M[,2]> 0,]
>  Policy.Number GWP_Max
> NA NA <NA>
> NA.1 NA <NA>
> NA.2 NA <NA>
> NA.3 NA <NA>
> NA.4 NA <NA>
> NA.5 NA <NA>
> NA.6 NA <NA>
> NA.7 NA <NA>
> NA.8 NA <NA>
> NA.9 NA <NA>
> NA.10 NA <NA>
> NA.11 NA <NA>
> Warning message:
> In Ops.factor(M[, 2], 0) : > not meaningful for factors
> > 
> somebady help me please!!!

Notice the warning:

Warning message:
In Ops.factor(M[, 2], 0) : > not meaningful for factors

So your data are not what you think they are.

Look at the output of

str(M)

and

sapply(M, class)

and see what types of variables are in M. If they are not numeric then
make them numeric. How you do that will depend on where these data
originated, how they were read in etc, none of which you have provided
information on.

HTH

G

> 
> thank you a lot
> Regards
> 
> 
>       
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> 
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