Task

Write a program to perform a conversion of the old Russian measures of length to the metric system   (and vice versa).



It is an example of a linear transformation of several variables.



The program should accept a single value in a selected unit of measurement, and convert and return it to the other units:

vershoks, arshins, sazhens, versts, meters, centimeters and kilometers.



Also see

   Old Russian measure of length


func convert (magnitude, unit) {
     var factor = Hash(
        tochka     => 0.000254,
        liniya     => 0.00254,
        diuym      => 0.0254,
        vershok    => 0.04445,
        piad       => 0.1778,
        fut        => 0.3048,
        arshin     => 0.7112,
        sazhen     => 2.1336,
        versta     => 1066.8,
        milia      => 7467.6,
        centimeter => 0.01,
        meter      => 1,
        kilometer  => 1000,
    )
 
    var meters = (magnitude * factor{unit.lc})
    say("#{magnitude} #{unit} to:\n", '-' * 40)
 
    for u,f in (factor.sort_by { |_,v| v }) {
        printf("%10s: %s\n", u, meters / f) if (u != unit.lc)
    }
}
 
convert(1, 'meter')
say('')
convert(1, 'milia')