# Transform vectors of spans (with duplication) to Visibility vector

Source:`R/tostring.R`

`spans_to_viscell.Rd`

Transform vectors of spans (with duplication) to Visibility vector

## Value

a logical vector the same length as `spans`

indicating
whether the contents of a string vector with those spans

## Details

The values of `spans`

are assumed to be repeated to such that
each individual position covered by the span has the repeated value.

This means that each block of values in `span`

must be of a length
at least equal to its value (i.e. two 2s, three 3s, etc).

This function correctly handles cases where two spans of the same size are next to each other; i.e., a block of four 2s represents two large cells each of which span two individual cells.

## Note

Currently no checking or enforcement is done that the vector of spans is valid in the sense described in the Details section above.

## Examples

```
spans_to_viscell(c(2, 2, 2, 2, 1, 3, 3, 3))
#> [1] TRUE FALSE TRUE FALSE TRUE TRUE FALSE FALSE
```