[R] Find solution for an error in the condition of if

[Duncan Murdoch]

On 30/04/2010 4:19 AM, anderson nuel wrote:
> Dear r-help,
>
> Could you help me to find a solution for this error:
>
> Il y a eu 50 avis ou plus (utilisez warnings() pour voir les 50 premiers)
>
>   
>> warnings()
>>     
> Messages d'avis :
> 1: In if ((data[pa, k] == df[, j]) & (data[ch, k] == i)) { ... :
>   la condition a une longueur > 1 et seul le premier élément est utilisé
>   

It's saying that the condition has length > 1 and only the first element 
is used.  This is probably coming from the first part of the test:  
data[pa,k] will be scalar, but df[,j] looks like a vector of every 
element in column j.  The result is a vector with as many entries as you 
have rows in df.  Only the first of them will be compared to data[pa, k].

Duncan Murdoch
> 2: In if ((data[pa, k] == df[, j]) & (data[ch, k] == i)) { ... :
>   la condition a une longueur > 1 et seul le premier élément est utilisé
>
>
> ch=3
> pa=c(1,2)
> r=2
> t=4
> nb=15
> ni=array(0,c( r,t))
>
> for ( i  in 1:r){
>
> for (j in 1:t ){
>
>     for (k in 1:nb){
>
>         if ( (data[pa,k]== df[,j]) & (data[ch,k]==i)){
>
>             ni[i,j]=ni[i,j]+1
>         }
>     }
> }
> }
>
> Best  Regards
>
> 	[[alternative HTML version deleted]]
>
>   
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