## R – Convert Character Vector into Integer Vector

To convert a given character vector into integer vector in R, call as.integer() function and pass the character vector as argument to this function. as.integer() returns a new vector with the character values transformed into integer values.

During conversion, each string value is converted into an integer value. It considers the special cases like considering a base value of 16 if the number in string is preceded by 0x, or 0X.

### Syntax

The syntax to use as.integer() to convert character vector `v1` to integer vector `v2` is

`v2 = as.integer(v1)`

### Examples

In the following program, we take a character vector in `v1`, and convert this to integer vector using as.integer(). We print the returned integer vector from as.integer(), and print the type of vector obtained programmatically using typeof() function.

example.R

```v1 <- c("1", "2", "0x44", "89")
v2 <- as.integer(v1)
print(v2)
print(typeof(v2))```

Output

```  1  2 68 89
 "integer"```

If there are NA values in the given character vector, then they remain unchanged with respect to their presence in the resulting vector from as.integer().

example.R

```v1 <- c("1", "2", NA)
v2 <- as.integer(v1)
print(v2)
print(typeof(v2))```

Output

```  1  2 NA
 "integer"```

If there are any string values which cannot be converted into a valid integer, then NA would be introduced for the respective value by coercion.

example.R

```v1 <- c("1", "2", "abc")
v2 <- as.integer(v1)
print(v2)
print(typeof(v2))```

The third value `"abc"` in vector `v1` cannot be converted to a valid number. Therefore, the third element in the resulting vector would be `NA`.

Output

```  1  2 NA
 "integer"```

### Conclusion

In this R Tutorial, we learned how to convert a character vector into integer vector, using as.integer() function, with the help of examples.