At a certain point I needed the maximum, minimum and mean of a list. Instead of calculating them one after the other I created a proc that calculates everything in one go. And also length and sum.

This is the proc:

======
proc listNumericStats {thisList} {
    set length [llength ${thisList}]
    if {${length} == 0} {
        error "List cannot be empty"
    }
    set max [lindex ${thisList} 0]
    set min ${max}
    set sum 0.
    foreach element ${thisList} {
        set sum [expr {${sum} + ${element}}]
        if {${element} < ${min}} {
            set min ${element}
        } elseif {${element} > ${max}} {
            set max ${element}
        }
    }
    dict set stats length ${length}
    dict set stats max    ${max}
    dict set stats mean   [expr {${sum} / ${length}}]
    dict set stats min    ${min}
    dict set stats sum    ${sum}
    return ${stats}
}
======

<<categories>>Numerics