r - Counting the number of elements with the values of x in a vector

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I have a vector of
numbers:

numbers <-
            c(4,23,4,23,5,43,54,56,657,67,67,435,

            453,435,324,34,456,56,567,65,34,435)

How
can I have R count the number of times a value x appears in the
vector?

Answer

You can just use
table():

>
            a <- table(numbers)

> a
numbers
 4 5 23
            34 43 54 56 65 67 324 435 453 456 567 657 
 2 1 2 2 1 1 2 1 2 1 3 1 1 1 1
            

Then you can subset
it:

>
            a[names(a)==435]
435 


            3

Or convert it into a
data.frame if you're more comfortable working with
that:

>
            as.data.frame(table(numbers))
 numbers Freq
1 4 2
2 5
            1
3 23 2

4 34
            2
...