Astronomical Unit (module) simple example for testing :)

[largo_winch]

although I have promised to go to christmas parties and to my family (they are shopping at the moment) I started last week this little exercise for (perhaps) a new module with some sense to use it for science. this first issue is hold very, very simple for using.

Astronimical Units (Astronomische Einheit: ae) is a fixed value. but it's easy to make some calculations for it. the glossary about astronomical units (au) you find in the thinbasic script file and some links too.

have fun with it. for next month I will check to make a gui for it with chance for user inputs.

'test module for astronomische einheit (astronomical unit) by largo_winch, 21.12.2011
'http://de.wikipedia.org/wiki/Astronomische_Einheit
'http://neo.jpl.nasa.gov/glossary/au.html
'    
'1 Astronomical Unit = 149 598 000 kilometers / 149.597.870.691 Meter.    
'
'-------------->

Uses "AstroUnit"

MyFunction()  

Function MyFunction()
  Dim ae1 As AstroUnit
  Dim ae2 As AstroUnit  
  Dim ae3 As AstroUnit  
  Dim ae4 As AstroUnit
  
  ae1 = New AstroUnit(1,1,1)
  ae2 = New AstroUnit(2,2,2)  
  ae3 = New AstroUnit(3,3,3)
  ae4 = New AstroUnit(4,4,4)
  
  MsgBox 0, ae1.ToString
  MsgBox 0, ae2.ToString  
  MsgBox 0, ae3.ToString  
  MsgBox 0, ae4.ToString
  
End Function   

'
'Glossary:
'
'--------->
'English:
'--------->

'ASTRONOMICAL UNIT (AU)

' 1 AU = 149,597,870.691 kilometers

'Definition: An Astronomical Unit is approximately the mean distance Between 
'the Earth And the Sun. It is a derived constant And used To 
'indicate distances within the solar system. 
'Its formal definition is the radius of an unperturbed 
'circular orbit a massless body would revolve about 
'the sun In 2*(Pi)/k days (i.e., 365.2568983.... days), 
'where k is defined As the Gaussian constant 
'exactly equal To 0.01720209895. 

'Since an AU is based On radius of a circular orbit, 
'one AU is actually slightly less than the average distance 
'Between the Earth And the Sun (approximately 150 million km Or 93 million miles).

'Historical Background: Tycho Brahe estimated the distance Between the 
'Sun And the Earth At 8 million kilometers (5 million miles). 
'Later, Johannes Kepler estimated the AU was At 24 million 
'kilometers (15 million miles). In 1672, Giovanni Cassini made a much 
'better estimate by Using Mars. By observing Mars from Paris 
'And having a colleague, Jean Richer, also observe Mars At the 
'same time In French Guiana In South America, Cassini determined 
'the parallax of Mars. From that Cassini was able To calculate the 
'distance from Earth To Mars, And Then the distance from Earth To the Sun. 
'Cassini calculated the AU To be At 140 million kilometers (87 million miles), 
'which is lower, but very close To the modern day Number. 

'-------->
'GERMAN:
'-------->

'Die AE war ursprünglich definiert als die Länge der 
'großen Halbachse der Erdbahn.
'Seit 1976 definiert die Internationale Astronomische Union (IAU) 
'die AE als den Radius einer kreisförmigen Umlaufbahn, 
'auf der ein Objekt mit vernachlässigbarer Masse und frei von Störungen 
'die Sonne In 2? / k Tagen (also In etwa einem Jahr) umläuft.
'[1] Dabei ist k die Gaußsche Gravitationskonstante, deren Wert 
'In Astronomischen Maßeinheiten definitionsgemäß exakt k = 0,017 202 098 95 beträgt.

'Die AE beträgt 149.597.870.691 Meter.    

'Der moderne Wert wurde mittels Radar- und anderen Distanzmessungen 
'von der Erde zu den Nachbarplaneten und zu Raumsonden bestimmt. 
'Früher wurde die AE hauptsächlich aus feinsten Winkelmessungen (Parallaxen) 
'abgeleitet, die zwischen weit entfernten Sternwarten zum Planeten Venus 
'und zu erdnahen Asteroiden gemessen wurden.      
'----------------------------------------------> FINE

new edit: in zip file you will find a german and an english version and source code of powerbasic "thinbasic_astroUnit.bas" example


2) @eros/petr/developer guys

in "thincore.inc" file there is a declaration like

  DECLARE FUNCTION  thinBasic_Parse1Number                LIB "thinCore.DLL" ALIAS "thinBasic_Parse1Number"               () AS EXT
  DECLARE FUNCTION  thinBasic_Parse2Numbers               LIB "thinCore.DLL" ALIAS "thinBasic_Parse2Numbers"              (Num1 AS EXT, Num2 AS EXT) AS EXT

but for "thinbasic_Parse1Number" (this function I wanted to choose, but didn't work as expected) it's better to use for future

 
thinBasic_Parse1Numbers              (Num1 AS EXT) AS EXT

so you can use and parse this number. in "thincore.inc" I guess it's not correct. without using one parsing number that's line is correct I am thinking:

thinBasic_ParseNumber              () AS EXT

bye, largo

[ErosOlmi]

Hi Largo,

thanks for your post. I've checked your source code and saw you perfectly used new Module classes.
I'm very happy about that and I can see there will be many many improvements in next thinBasic version on this side.

The main difference between thinBasic_ParseNumber and thinBasic_Parse1Number is that

1. thinBasic_ParseNumber only parse a numeric expression so if you have to parse a single numeric function parameter you also need to parse open and close parenthesis ()
2. thinBasic_Parse1Number not only parse a numeric expression but it also parse () if optionally present

Also another important difference is that:

1. thinBasic_ParseNumber is a SUB and accepts a BYREF Extended numeric variable so you cannot use thinBasic_ParseNumber directly
2. thinBasic_Parse1Number is a FUNCTION and it doesn't need any passing variable but instead it returns the result of the numeric expression it has parsed and resolved. It can also be used directly as parameter of other functions.

Example using thinBasic_ParseNumber parsing something like ... (NumericParam)

    Local pp      As Byte
    Local eNum    As Ext
    '---Optionally checks if there is a (
    pp = thinBasic_CheckOpenParens_Optional
    thinBasic_ParseNumber eNum
    if pp then thinBasic_CheckCloseParens_Mandatory

Same example now using thinBasic_Parse1Number parsing something like ... (NumericParam)

    Local eNum    As Ext
    eNum = thinBasic_Parse1Number

It depends on the situations what is better to use for the programmer.

Ciao
Eros