

Python and Tcl - pmarin
http://commandline.org.uk/python/python-and-tcl/

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pmarin
The larger version can be done without the expr command in the _if_ statement:

    
    
       proc nearestneighbours {numlist number} {
        # For a given number, find the nearest lower and higher numbers in
        # a given (ordered) list of numbers.
        set left 0
        set right 1000000000
    
        foreach i $numlist {
            if { $i < $number && $i > $left} {set left $i} elseif {
             $i > $number && $i < $right} {set right $i}
        } ;# end foreach
    
        set nearest [list $left $right]
        return $nearest
        } ;# end proc findnearest
    
        proc main {} {
        # Demo when called directly.
        set mylist [list "58163" "62140" "66139" "70280" "74371" "78525" "82426" "86584" "90650" "94749"]
        set number 67000
        set highlow [nearestneighbours $mylist $number]
    
        puts "Lower: [lindex $highlow 0]"
        puts "Higher: [lindex $highlow 1]"
        } ;# end proc main
    
       main

