# following statements can be pasted into eTCL console
    set testcase_1   [ eval expr  ( 1+1 +1+1)/4  ]  # 1 square meters
    set testcase_2  [ eval expr  ( 2+2 +4+4)/4 ]   # 3 square meters
    set testcase_3   [ eval expr ( 3+3 +5+5)/4  ]  # 4 square meters
    set testcase_1_perimeter   [ eval expr  ( 1+1 +1+1) ]  # 4 square meters
    set testcase_2_perimeter   [ eval expr  ( 2+2 +4+4) ]   # 12 square meters
    set testcase_3_perimeter    [ eval expr ( 3+3 +5+5)  ]  # 16 square meters

    set volume_bowl  [eval expr (5./60.)*(5./60.)*(4.*60.+48.) ]  #  2 sila in Babylonian calculation
    set conventional_vol? [eval expr 2.*((.5*.5/(3.*4.))*.09) ] # 0.00375 liters per m*m
    set conv_circle [eval expr 1.5*1.5*(1/12.) ] # text answer 11/60+15/3600, decimal 0.1875
    set strange_formula [eval expr $area*$area*(4.*60.+48.)]  # possible sila per kus*kus factor
    45 carrying baskets (45*25=1125kg) per 1us (360 meters) per workday
    1_15 talents dirt (1_15=1/60+15/3600=37.5 kg) for 1 dana (1 dana=beru=10.8 km) per workday
    6 bricks (b=8.5 minas>>6*8.5*0.4977kg,25.3827) for beru 10.8 kilometers per day
    large basket (dusu)  =2_13_20 volume shekel=1/27 volume shekel=13.33 kilograms=11.1 liters
    small basket = 1_4 volume shekel=1/48 volume shekel=7.5 kilograms=6.25 liters
    1 volume shekel = 300 liters = 12 talents =12*30=360 kilograms
    1 talent =12 volume shekels 

    # following statements can be pasted successively into eTCL console
    proc pi {} {expr acos(-1)}  
    set inner_cylinder_a=b*(c*c/d*d)_  [*  0.1790[/  [* 1. 1.  ] [* 4. 4.  ]   ]] # 0.0111
    set hollow_cylinder_a=b*(c*c/d*d)_  [*  0.1790[- 1. [/  [* 1. 1.  ] [* 4. 4.  ]]   ]] # 0.1678 
    set inner_cylinder_  [ eval expr [pi]*.0597*.0597*1 ] # 0.0111
    set outer_cylinder_  [ eval expr [pi]*.2387*.2387*1 ] # 0.1790
    set overshoot_error [eval expr (2.5424/2.40909)-1. ] # 0.05533624729669717
    set error_log_coefficient [eval expr (1.-3.125/[pi])*100.] # undershoot 0.52 percent error
    set error_3_for_PI_coefficient [eval expr (1.-3.0/[pi])*100.] # undershoot 4.5 percent error
    set log_coefficient_reciprocal [ eval expr (1./4.*[pi]) ] # 0.7853981633974483
    set imla_reciprocal_PI_coefficient [ eval expr (1./6.*[pi]) ] # 0.5235987755982988

        # pretty print from autoindent and ased editor
        # Sumerian Surveyor Formula calculator
        # written on Windows XP on eTCL
        # working under TCL version 8.5.6 and eTCL 1.0.1
        # gold on TCL WIKI, 15may2016
        package require Tk
        namespace path {::tcl::mathop ::tcl::mathfunc}
        frame .frame -relief flat -bg aquamarine4
        pack .frame -side top -fill y -anchor center
        set names {{} {length L1 meters :} }
        lappend names {length L2 meters :}
        lappend names {width W1 meters: }
        lappend names {width W2 meters :}
        lappend names {answers: average length meters:}
        lappend names {average width meters: }
        lappend names {surface area square meters: }
        lappend names {surface area square meters :}
        foreach i {1 2 3 4 5 6 7 8} {
            label .frame.label$i -text [lindex $names $i] -anchor e
            entry .frame.entry$i -width 35 -textvariable side$i
            grid .frame.label$i .frame.entry$i -sticky ew -pady 2 -padx 1 }
        proc about {} {
            set msg "Calculator for Sumerian Surveyor 
            from TCL WIKI,
            written on eTCL "
            tk_messageBox -title "About" -message $msg } 
       proc pi {} {expr acos(-1)}       
       proc calculate {     } {
            global answer2
            global side1 side2 side3 side4 side5
            global side6 side7 side8
            global testcase_number
            global average_length average_width total_surface_area 
            incr testcase_number 
            set side1 [* $side1 1. ]
            set side2 [* $side2 1. ]
            set side3 [* $side3 1. ]
            set side4 [* $side4 1. ]
            set side5 [* $side5 1. ]
            set side6 [* $side6 1. ]
            set side7 [* $side7 1. ]
            set side8 [* $side8 1. ]
            set length1 $side1  
            set length2 $side2
            set width1 $side3 
            set width2 $side4 
            set average_length [/ [+ $length1 $length2 ] 2. ]
            set average_width [/ [+  $width1 $width2 ] 2. ]
            set total_surface_area [/ [+ $length1 $length2 $width1 $width2 ] 4. ]
            set perimeter [+ $length1 $length2 $width1 $width2 ] 
            set side5 $average_length
            set side6 $average_width
            set side7 $perimeter
            set side8 $total_surface_area
                    }
        proc fillup {aa bb cc dd ee ff gg hh} {
            .frame.entry1 insert 0 "$aa"
            .frame.entry2 insert 0 "$bb"
            .frame.entry3 insert 0 "$cc"
            .frame.entry4 insert 0 "$dd"
            .frame.entry5 insert 0 "$ee"
            .frame.entry6 insert 0 "$ff" 
            .frame.entry7 insert 0 "$gg"
            .frame.entry8 insert 0 "$hh" 
             }
        proc clearx {} {
            foreach i {1 2 3 4 5 6 7 8 } {
                .frame.entry$i delete 0 end } }
        proc reportx {} {
            global side1 side2 side3 side4 side5
            global side6 side7 side8 
            global testcase_number
            global average_length average_width total_surface_area
            console show;
            puts "%|table $testcase_number|printed in| tcl wiki format|% "
            puts "&| quantity| value| comment, if any|& "
            puts "&| testcase number:|$testcase_number | |&"
            puts "&| $side1 :|length L1 meters meters |   |&"
            puts "&| $side2 :|length L2 meters | |& "
            puts "&| $side3 :|width W1 meters| |& "
            puts "&| $side4 :|width W2 meters| |&"
            puts "&| $side5 :|average length meters | |&"
            puts "&| $side6 :|average width meters |  |&"
            puts "&| $side7 :|perimeter meters|  |&"
            puts "&| $side8 :|surface area square meters|  |&" 
            }
        frame .buttons -bg aquamarine4
        ::ttk::button .calculator -text "Solve" -command { calculate   }
        ::ttk::button .test2 -text "Testcase1" -command {clearx;fillup 1.0 1.0 1.0 1.0  1.0 1.0 1.0 1.0}
        ::ttk::button .test3 -text "Testcase2" -command {clearx;fillup 2. 2. 4.0 4.0   4.0  2.0 3.0 3.0 }
        ::ttk::button .test4 -text "Testcase3" -command {clearx;fillup 3. 3. 5.0 5.0   4.0 2.0  4.0 4.0 }
        ::ttk::button .clearallx -text clear -command {clearx }
        ::ttk::button .about -text about -command about
        ::ttk::button .cons -text report -command { reportx }
        ::ttk::button .exit -text exit -command {exit}
        pack .calculator  -in .buttons -side top -padx 10 -pady 5
        pack  .clearallx .cons .about .exit .test4 .test3 .test2   -side bottom -in .buttons
        grid .frame .buttons -sticky ns -pady {0 10}
        . configure -background aquamarine4 -highlightcolor brown -relief raised -border 30
        wm title . "Sumerian Surveyor Area Formula Calculator"

  puts " %| testcase $testcase_number | value| units |comment |%"
  puts " &| volume| $volume| cubic meters |based on length $side1 and width $side2   |&"