Using filter_ in dplyr where both field and value are in variables

Question

I want to filter a dataframe using a field which is defined in a variable, to select a value that is also in a variable. Say I have

df <- data.frame(V=c(6         


        

Answer 1

Here's an alternative with base R, which is maybe not very elegant, but it might have the benefit of being rather easily understandable:

df[df[colnames(df)==fld]==sval,]
#  V Unhappy
#2 1       Y
#3 5       Y
#4 3       Y