when you only want to get a vector field (e.g., U) 

Nice jobs! One suggestion of mine is to change

```cpp
forAll (allScalarFields[0], cellI)
```

to

```cpp
forAll (mesh.C(), cellI)
```

to get rid of the error when you only want to get a vector field (e.g., U) with the following command:

```bash
foam2Columns -vectorFields "(U)" -latestTime
```

