Consider a vector of numbers:

```num <- c(2,13,7,13,51,43,44,76,647,37,367,435,
443,425,314,31,416,16,367,65,44,425)```

How can I count the number of times a value 'x' appears in the vector with R? Apr 12, 2018 95 views

## 2 answers to this question.

You have various options to count the number of times a number occurs:

One of them is to use table():

```z <- table(num)
> z
num
2  7  13  16  31  37  43  44  51  65  76  314  367  416  425  435  443  647
1   1   2   1   1   1   1   2  1  1  1
1   2   1   1   1   1   1   1
```

Then you can subset it, for the number you want the count for:

```z[names(z)==367]
367
2```

The second option is to convert it into a data.frame

```as.data.frame(table(num))
num Freq
1        2    1
2        7    1
3       13    2
4       16    1
...``` answered Apr 12, 2018 by
• 6,140 points

Use dplyr function group_by().

```> n = as.data.frame(num)
> n %>% group_by(num) %>% count()```
```     num     n
<dbl> <int>
1     2     1
2     7     1
3    13     2
4    16     1
5    31     1
6    37     1
7    43     1
8    44     2
9    51     1
10    65     1
11    76     1
12   314     1
13   367     2
14   416     1
15   425     2
16   435     1
17   443     1
18   647     1
``` answered Aug 21 by anonymous
• 25,900 points

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