shadow_shift where there is no variance

[njtierney]

Previously in #36 I worked out how to handle cases where there is only one complete value.

Now I need to work out a way to handle cases where there is no variance

library(naniar)

shadow_shift(c(NA,4,4))
#> [1] 4 4 4

It performs find when there is some small variance

shadow_shift(c(NA,4,3))
#> [1] 2.884298 4.000000 3.000000
shadow_shift(c(NA,4,NA))
#> [1] 3.424959 4.000000 3.457942

[njtierney]

This now works!

library(narnia)

shadow_shift(c(NA,4,4))
#> [1] 3.740455 4.000000 4.000000
shadow_shift(c(NA,4,3))
#> [1] 2.881757 4.000000 3.000000
shadow_shift(c(NA,4,NA))
#> [1] 3.731255 4.000000 3.506998