Map range

editable example

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ghul

use IO.Std.write_line

use Ghul.Pipes

map_range(

(a1, a2): (double, double),

(b1, b2): (double, double),

s: double

) -> double =>

b1 + (s - a1) * (b2 - b1) / (a2 - a1)

(0::10)

|> map(s =>

(s, mapped = map_range((0.0D, 10.0D), (-1.0D, 0.0D), cast(s))))

|> each(((s, mapped)) => write_line("{s} maps to {mapped:F1}"))

0 maps to -1.0
1 maps to -0.9
2 maps to -0.8
3 maps to -0.7
4 maps to -0.6
5 maps to -0.5
6 maps to -0.4
7 maps to -0.3
8 maps to -0.2
9 maps to -0.1
10 maps to 0.0