How do add a column in a data frame in R

Question

I have imported data from a file into a data frame in R. It is something like this.

Name      Count   Category
A         100     Cat1
C         10      Cat2
D         40      Cat1 
E         30      Cat3
H         3       Cat3
Z         20      Cat2
M         50      Cat10

So now i want to add the Category column depending on the values in the column Name. So something like if Name = (A, D), Category = 'Cat1' etc.

This is only a simple example I am giving. I have a large number of Names and Categories so I want a compact syntax. How can I do this?

Edit: I've changed the example to better suit my needs as the name can be anything not numeric. Sorry for not being too clear before.

Answer 1

You can use ifelse. If your data frame were called df you would do:

df$cat <- ifelse(df$name<100, "Ones", "Hundreds")
df$cat <- ifelse(df$name<1000, df$cat, "Thousands")