Updated 2017-03-09 23:03:39 by gold

## Introduction edit

gold Here is some eTCL starter code for the calculating the mass of the earth from the moon orbit and lunar velocity. The impetus for these calculations was checking new discoveries in astronomy. Most of the testcases involve experiments or models, using assumptions and rules of thumb.

### Pseudocode Section

```    pseudocode can be developed from rules of thumb.
pseudocode: enter radius of moon orbit, moon velocity, gravity constant
pseudocode: output mass of earth in kilograms, metric tons
pseudocode: need diameter of moon orbit also
pseudocode: rules of thumb can be 3 to 15 percent off, partly since g..in g..out.
pseudocode: need test cases > small,medium, giant
pseudocode: need testcases within range of expected operation.
pseudocode: are there any cases too small or large to be solved? ```

### 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

mass of earth table printed in tcl wiki format
quantity value comment, if any
testcase number 1
radius of lunar orbit, meters: 3.75E8
velocity of moon in orbit, meters: 1000.
gravitational constant m**3/kg-sec*sec : 6.67384E-11
answers: lunar orbit diameter meters : 7.5E8
planet mass kilograms: 5.618e+24
planet mass kilograms: 5.618e+24
planet mass metric tons: 5.6183e+21

#### Testcase 2

mass of Saturn from orbit of Titan table printed in tcl wiki format
quantity value comment, if any
testcase number 2
radius of Titan orbit, meters: 1.221E9
velocity of Titan in orbit, meters: 5569.7
gravitational constant m**3/kg-sec*sec : 6.67384E-11
answers: Titan orbit diameter meters : 2442000000.0
planet Saturn mass kilograms: 5.675e+26
planet Saturn kilograms: 5.6756e+26
planet Saturn metric tons: 5.675e+23

#### Testcase 3

mass of Jupiter from orbit of Ganymede printed in tcl wiki format
quantity value comment, if any
testcase number 3
radius of Ganymede orbit, meters: 1.070E9
velocity of Ganymede in orbit, meters: 10879
gravitational constant m**3/kg-sec*sec : 6.67364E-11
answers: Ganymede orbit diameter meters : 2140000000.0
planet Jupiter mass kilograms: 1.897e+27
planet Jupiter mass kilograms: 1.897e+27
planet Jupiter mass metric tons: 1.897e+24

### References:

• Earth Fact sheet from NASA [1]
• Moon fact sheet from NASA[2]

## Appendix Code edit

### appendix TCL programs and scripts

```        # pretty print from autoindent and ased editor
# planet mass calculator
# written on Windows XP on eTCL
# working under TCL version 8.5.6 and eTCL 1.0.1
# gold on TCL WIKI , 2may2014
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 {{} { radius of lunar orbit  meters:} }
lappend names { velocity of moon in orbit  meters per second:}
lappend names { gravitational constant  m**3/kg-sec*sec: }
lappend names { answers: lunar orbit diameter meters  :}
lappend names { earth mass kilograms :}
lappend names { earth mass kilograms :}
lappend names { earth mass metric tons:}
foreach i {1 2 3 4 5 6 7} {
label .frame.label\$i -text [lindex \$names \$i] -anchor e
entry .frame.entry\$i -width 35 -textvariable side\$i
proc pi {} {expr acos(-1)}
set msg "Calculator for Mass of Planet
from TCL WIKI,
written on eTCL "
tk_messageBox -title "About" -message \$msg }
proc calculate { } {
global side1 side2 side3 side4 side5
global side6 side7 testcase_number
incr testcase_number
set lvelocity \$side2
set grav_const \$side3
set diameter1 [* \$lradius  2. ]
set side4 \$diameter1
set mass [/ [* \$lradius \$lvelocity \$lvelocity ] \$grav_const ]
set side5 \$mass
set side6 \$mass
set side7 [* \$mass .001 ]
return \$side5
}
proc fillup {aa bb cc dd ee ff gg} {
.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"}
proc clearx {} {
foreach i {1 2 3 4 5 6 7} {
.frame.entry\$i delete 0 end } }
proc reportx {} {
global side1 side2 side3 side4 side5
global side6 side7 testcase_number
console show;
puts "%| table |printed in| tcl wiki format|% "
puts "&| quantity| value| comment, if any|& "
puts "&| testcase number| \$testcase_number||& "
puts "&| radius of lunar orbit, meters:| \$side1 ||&"
puts "&| velocity of moon in orbit, meters:| \$side2||& "
puts "&| gravitational constant m**3/kg-sec*sec :| \$side3||& "
puts "&| answers:  lunar orbit diameter meters :| \$side4 ||&"
puts "&| planet mass kilograms:| \$side5||& "
puts "&| planet mass kilograms:| \$side6 ||&"
puts "&| planet mass metric tons:| \$side7 ||&"
}
frame .buttons -bg aquamarine4
::ttk::button .calculator -text "Solve" -command { calculate   }
::ttk::button .test2 -text "Testcase1" -command {clearx;fillup 3.75E8 1000. 6.67384E-11  7.5E8  5.6E21 5.6E21  5.6E21 }
::ttk::button .test3 -text "Testcase2" -command {clearx;fillup 3.75E8 1000. 6.67384E-11  7.5E8  5.6E21 5.6E21  5.6E21 }
::ttk::button .test4 -text "Testcase3" -command {clearx;fillup 3.75E8 1000. 6.67364E-11  7.5E8  5.6E21 5.6E21  5.6E21  }
::ttk::button .clearallx -text clear -command {clearx }
::ttk::button .cons -text report -command { reportx }
::ttk::button .exit -text exit -command {exit}
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 . "Planet Mass 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 (which 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   |&"  ```