Checks if a partial ranking is preserved in the ranking induced by `scores`

.

## Arguments

- P
A partial ranking as matrix object calculated with neighborhood_inclusion or positional_dominance.

- scores
Numeric vector containing the scores of a centrality index.

## Details

In order for a score vector to preserve a partial ranking, the following
condition must be fulfilled:
`P[u,v]==1 & scores[i]<=scores[j]`

.

## Examples

```
library(igraph)
# standard measures of centrality preserve the neighborhood inclusion preorder
data("dbces11")
P <- neighborhood_inclusion(dbces11)
is_preserved(P, degree(dbces11))
#> [1] TRUE
is_preserved(P, betweenness(dbces11))
#> [1] TRUE
is_preserved(P, closeness(dbces11))
#> [1] TRUE
```