number(accuracy = NULL) heuristic too precise?

[nicolaspayette]

scales::number(c(10, 20, 30))
#> [1] "10" "20" "30"
scales::number(c(5, 10, 15))
#> [1] "5.0"  "10.0" "15.0"

When the smallest interval is >= 1 and < 10, the heuristic computes an accuracy of 0.1.

This might be the intended behaviour, but I find it puzzling: why would the extra decimal be desirable?

The question has been raised in passing before, but I didn't find any other discussion.

If this behaviour is modified, it might also make sense to change the default in label_number_si() to accuracy = NULL, since the current default of accuracy = 1 gives results like:

scales::label_number_si()(c(1.5E6, 2E6, 2.5E6))
#> [1] "2M" "2M" "2M"

[davidchall]

@nicolaspayette - Please note that #235 changes the default of label_number_si() to accuracy = NULL.

[nicolaspayette]

@davidchall, #235 looks fantastic. And maybe having accuracy = NULL as a default will bring more attention to the present issue.