Reshape dataframe without timevar from long to wide format in R

Question

I have a data frame as follows:

   Name          MedName
  Name1    atenolol 25mg
  Name1     aspirin 81mg
  Name1 sildenafil 100mg
  Name2    atenolol 50mg
  Name2   enalapril 20mg

I would like to get the data in the below format:

   Name   medication1    medication2      medication3
  Name1 atenolol 25mg   aspirin 81mg sildenafil 100mg
  Name2 atenolol 50mg enalapril 20mg             NA

When I tried using dcast(dataframe, Name ~ MedName, value.var='MedName') 

I just get a bunch of columns that are flags of the medication names (values that get transposed are 1 or 0) example:

 Name  atenolol 25mg  aspirin 81mg
Name1              1             1
Name2              0             0 

How do I reshape using the dcast function

Answer 1

Assuming that the data is in the object dataset, you can try the below code.

library(plyr)
## Add a medication index
data_with_index <- ddply(dataset, .(Name), mutate, 
                         index = paste0('medication', 1:length(Name)))    
dcast(data_with_index, Name ~ index, value.var = 'MedName')

##    Name   medication1    medication2      medication3
## 1 Name1 atenolol 25mg   aspirin 81mg sildenafil 100mg
## 2 Name2 atenolol 50mg enalapril 20mg             <NA>