[R] Use of ifelse for indicating specific rownumber

[Eik Vettorazzi]

why use ifelse? Shouldn't

b2$totalvac<-rep(0,1521)
b2$totalvac[i]<-1

do the trick?

joe1985 schrieb:
> Hello
>
> I have a dataset named "b2" with 1521 rows, in that dataset i have 64 rows
> containing specific information.
>
> the rownumbers with specific info are:
>
> + i
>  [1]   22   53  104  127  151  196  235  238  249  250  263  335  344  353 
> 362  370  389  422  458  459  473  492  502  530  561  624  647  651  666 
> 671
> [31]  715  784  791  807  813  823  830  841  862  865 1036 1051 1062 1068
> 1092 1109 1171 1187 1283   1293 1325 1335 1342 1360 1379 1414 1419 1425 1447
> 1452
> [61] 1465 1489 1512 1518
>
> So what i want is that everytime the rownumber equals a number in "i" (which
> obviously indicate a rownumber i b2), i want it indicated in a vector called
> b2$totalvac. Fx. in rownumber 22 in b2 the 
> b2$totalvac vector should have the value 1.
>
> So thougth of  b2$totalvac <- ifelse(,1,0), but i don't what to put as the
> "if"-sentence.
>
> Hope you can help me
>   

-- 
Eik Vettorazzi
Institut für Medizinische Biometrie und Epidemiologie
Universitätsklinikum Hamburg-Eppendorf

Martinistr. 52
20246 Hamburg

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