Question

anyone can explain why this code in R doesn't work? i also tried to use filter function, no hope either!

b <- subset(sub,NEIGHBORHOOD == "HARLEM-CENTRAL")

the name of the variable is correct, the condition. is correct too.

Answer 1

b <- subset(sub,NEIGHBORHOOD == "HARLEM-CENTRAL",select=c(columnname1,columnname2,columnname3))

You have to add a select attribute also which contains the columns from sub. Since you have not provided the dataframe sub, I have simply given columnname1, columnname2, columnname3. There give the actual column names in sub which is your original data frame.

Example

x<-data.frame("roll"=1:11,

"name"=c("Jack","Jill","Jeeva","Smith","Bob","Smith","John","Mathew","Charles","Zen","Yug"),

"age"=c(20,22,30,28,30,21,19,18,25,25,29))

Here x is my dataframe.

newdata <- subset(x, age >= 25 & age < 30,select=c(roll,name,age)) will produce the following results.

# subset(x, age >= 25 & age < 30,select=c(roll,name,age))

   roll    name age

4     4   Smith 28

9     9 Charles 25

10   10     Zen 25

11   11     Yug 29