Updated 2016-05-04 19:06:59 by gold

Sales Optimal Lot Order Size and eTCL Slot Calculator Demo Example  edit

This page is under development. Comments are welcome, but please load any comments in the comments section at the bottom of the page. Please include your wiki MONIKER in your comment with the same courtesy that I will give you. Its very hard to reply intelligibly without some background of the correspondent. Thanks,gold

gold Here is some eTCL starter code for calculating the Optimal Lot Order Size. Most of the testcases involve replicas or models, using assumptions and rules of thumb.

The inventory_cost equals (ordering_cost*units_sold)/order_quantity + (unit_price*units_sold +holding_cost*order_quantity/2. The optimal order_quantity equals sqrt < (2.*ordering_cost*units_sold)/holding_cost>. In the calculator the holding_cost is calculated over a time period, usually 7 days. The holding_cost is dollars per unit per time interval.

Pseudocode and Equations

  price? = raw materials + labor  +  profit
  price? = raw materials + heat process
  price? = raw materials + labor 
  average price per unit  = revenue  / units sold

Testcases Section

In planning any software, it is advisable to gather a number of testcases to check the results of the program. The math for the testcases can be checked by pasting statements in the TCL console. Aside from the TCL calculator display, when one presses the report button on the calculator, one will have console show access to the capacity functions (subroutines).

Testcase 1

table 1printed in tcl wiki format
quantity value comment, if any
testcase number:1
10.0 :cost of ordering 1 item in dollars
50.0 :number of sales per time interval
5.0 :holding cost per time interval
7.0 : time interval days usually 7
1.0 :inventory item trial value
10.0:answers: lot size
100.0 : order value dollars
1.40 :expected interval for empty shelf days
10.0 :discounted inventory total dollars trial item usually 1 d.


Testcase 2

table 2printed in tcl wiki format
quantity value comment, if any
testcase number:2
100.0 :cost of ordering 1 item in dollars
1000.0 :number of sales per time interval
10.0 :holding cost per time interval
7.0 : time interval days usually 7
1.0 :inventory item trial value
100.0:answers: lot size
10000.0 : order value dollars
0.700 :expected interval for empty shelf days
100.0 :discounted inventory total dollars trial item usually 1 d.


Testcase 3

table 3printed in tcl wiki format
quantity value comment, if any
testcase number:3
10.0 :cost of ordering 1 item in dollars
100.0 :number of sales per time interval
10.0 :holding cost per time interval
7.0 : time interval days usually 7
1.0 :inventory item trial value
10.0:answers: lot size
100.0 : order value dollars
0.700 :expected interval for empty shelf days
10.0 :discounted inventory total dollars trial item usually 1 d.


Screenshots Section

figure 1.


References:

  • Stat

Appendix Code edit

appendix TCL programs and scripts

        # pretty print from autoindent and ased editor
        # Wilson lot order size sales calculator
        # written on Windows XP on eTCL
        # working under TCL version 8.5.6 and eTCL 1.0.1
        # gold on TCL WIKI, 10oct2014
        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 {{} {cost of ordering 1 item in dollars:} }
        lappend names {number of sales per time interval :}
        lappend names {holding cost each item per time interval: }
        lappend names {optional, time interval days usually 7 :}
        lappend names {optional, wholesale item at inventory trial $1 :}
        lappend names {answers: optimum lot size, number of items: }
        lappend names {order value dollars: }
        lappend names {expected interval until empty shelf days :}
        foreach i {1 2 3 4 5 6 7 8} {
            label .frame.label$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 lot order size 
            from TCL WIKI,
            written on eTCL "
            tk_messageBox -title "About" -message $msg }       
       proc calculate {     } {
            global answer2
            global side1 side2 side3 side4 side5
            global side6 side7 side8
            global discounted_inventory
            global testcase_number
            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 cost_order  $side1  
            set number_sales $side2
            set holding_cost $side3  
            set quantity  [/ [* $cost_order $number_sales ] $holding_cost]
            set  quantity [sqrt $quantity ]
            set side6 $quantity 
            set order_cost [* $quantity $cost_order ]
            set side7 $order_cost
            set interval $side4 
            set shelf_life_per_interval [/ $quantity $number_sales ]
            set shelf_life_days [* $shelf_life_per_interval $interval ]
            set side8 $shelf_life_days
            set inventory_trial_value $side5
            set discounted_inventory [* $inventory_trial_value $quantity      ]                    }
        proc fillup {aa bb cc dd ee ff gg hh} {
            .frame.entry1 insert 0 "$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 discounted_inventory
            console show;
            puts "%|table $testcase_number|printed in| tcl wiki format|% "
            puts "&| quantity| value| comment, if any|& "
            puts "&| testcase number:|$testcase_number | |&"
            puts "&| $side1 :|cost of ordering 1 item in dollars |   |&"
            puts "&| $side2 :|number of sales per time interval | |& "
            puts "&| $side3 :|holding cost per time interval| |& "
            puts "&| $side4 :| time interval days usually 7 |  |&"
            puts "&|$side5 :|inventory item trial value |  |&"
            puts "&| $side6:|answers: lot size |  |&"
            puts "&| $side7 :| order value dollars|  |&"
            puts "&| $side8  :|expected interval for empty shelf days|  |&"
            puts "&| $discounted_inventory  :|discounted inventory   total dollars |trial item usually  1 d. |&"              
        
            }
        frame .buttons -bg aquamarine4
        ::ttk::button .calculator -text "Solve" -command { calculate   }
        ::ttk::button .test2 -text "Testcase1" -command {clearx;fillup 10.0 50.0 5.0 7.0  1.0 10.0 100. 1.4}
        ::ttk::button .test3 -text "Testcase2" -command {clearx;fillup 100.0 1000.0 10.0 7.0   1.0  100. 1.E4 0.70 }
        ::ttk::button .test4 -text "Testcase3" -command {clearx;fillup 10.00 100.0 10.0 7.0   1.0 10.0  100. 0.70 }
        ::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 . "Lot Order Size Calculator "

Pushbutton Operation

For the push buttons, the recommended procedure is push testcase and fill frame, change first three entries etc, push solve, and then push report. Report allows copy and paste from console.

For testcases in a computer session, the eTCL calculator increments a new testcase number internally, eg. TC(1), TC(2) , TC(3) , TC(N). The testcase number is internal to the calculator and will not be printed until the report button is pushed for the current result numbers. The current result numbers will be cleared on the next solve button. The command { calculate; reportx } or { calculate ; reportx; clearx } can be added or changed to report automatically. Another wrinkle would be to print out the current text, delimiters, and numbers in a TCL wiki style table as
  puts " %| testcase $testcase_number | value| units |comment |%"
  puts " &| volume| $volume| cubic meters |based on length $side1 and width $side2   |&"  

gold This page is copyrighted under the TCL/TK license terms, this license.

Comments Section edit

Please place any comments here, Thanks.