I'm trying to join two columns of a SpatialDataFrame (shapefile) into one using the R program, but in both columns there are empty spaces, when they are together with the name plus NA, however I would like the NAs not to appear in my new column. I used the paste function.
something like this:

```
  This is the structure of my SpatialDataFrame:

  ID           city                city2
1  1      saõ paulo                 <NA>
2  2      Rio de Janeiro            <NA>
3  3           <NA>            Belo Horizonte
4  4           <NA>            Curitiba

```

obs. my original data is not this and has more columns

I used this:

```
data$newCity <- paste(data$city, data$city2) # I don't want to show in my data Na

```

1.

```
ID          city          city2                newCity
  1      saõ paulo         <NA>            saõ paulo NA
  2  Rio de Janeiro        <NA>            Rio de Janeiro NA
  3        <NA>       Belo Horizonte       NA Belo Horizonte
  4        <NA>       Curitiba             NA Curitiba

```

In fact this would be the desired result:

```
ID          city          city2                 newCity
 1      saõ paulo         <NA>                saõ paulo
 2    Rio de Janeiro      <NA>               Rio de Janeiro
 3        <NA>         Belo Horizonte         Belo Horizonte
 4        <NA>          Curitiba              Curitiba

```