Units: Difference between revisions

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Here some reading about units:
[http://en.wikipedia.org/wiki/Imperial_units]
[http://en.wikipedia.org/wiki/SI_derived_unit]
*[http://en.wikipedia.org/wiki/International_System_of_Units SI system]
[http://en.wikipedia.org/wiki/Degree_%28angle%29]
*[http://en.wikipedia.org/wiki/Imperial_units Imperial units]
[http://en.wikipedia.org/wiki/International_System_of_Units]
*[http://en.wikipedia.org/wiki/SI_derived_unit SI derived units]
*[http://en.wikipedia.org/wiki/Degree_%28angle%29 angle units]

== Examples ==

# -- some examples of the FreeCAD unit translation system --
# make a shorcut for the examples
tu = App.translateUnit
# 10 meteres in internel numbers
tu('10 m')
# doing math
tu('3/8 in')
# combined stuff
tu('100 km/h')
# transfer to other units
tu('100 km/h')/tu('m/s')
# derived units (Ohm)
tu('m^-2*kg*s^-3*A^1')
# or
tu('(kg*A)/(m^2*s^3)')


== supported units ==
Here the in FreeCAD defined units so far. Its easy to add one. The definition is here[http://free-cad.svn.sourceforge.net/viewvc/free-cad/trunk/src/Base/UnitsApi.l?view=markup].
"mm" 1.0; // milimeter (internal standard length)
"m" 1000.0; // meter
"cm" 10.0; // centimeter
"dm" 100.0; // decimeter
"km" 1000000.0; // kilometer
"in" 25.4; // inch
"fo" 304.8; // foot
"th" 0.0254; // thou
"yr" 914.4; // yard
"kg" 1.0; // kilogramm (internal standard mass)
"g" 0.001; // gramm
"mg" 0.000001; // miligramm
"t" 1000.0; // ton
"lb" 0.45359237; // pound
"oz" 0.45359237; // ounce
"st" 6.35029318; // Stone
"cwt" 50.80234544;// hundredwights
"°" 1.0; // degree (internal standard angle)
"rad" M_PI/180; // radian
"gon" 360.0/400.0;// gon
"s" 1.0; // second (internal standard time)
"min" 60.0; // minute
"h" 3600.0; // hour
"A" 1.0; // second (internal standard electric current)
"K" 1.0; // second (internal standard thermodynamic temperature)
"cd" 1.0; // second (internal standard luminous intensity)
"mol" 1.0; // second (internal standard amount of substance)

"mL" 1.0; // microliter mm^3 (derived standard volume)
"L" 1000000.0; // Liter dm^3

Revision as of 14:52, 7 January 2010

Here some reading about units:

Examples

# -- some examples of the FreeCAD unit translation system --
# make a shorcut for the examples
tu = App.translateUnit

# 10 meteres in internel numbers
tu('10 m')
# doing math
tu('3/8 in')
# combined stuff
tu('100 km/h')
# transfer to other units
tu('100 km/h')/tu('m/s')
# derived units (Ohm)
tu('m^-2*kg*s^-3*A^1')
# or
tu('(kg*A)/(m^2*s^3)')


supported units

Here the in FreeCAD defined units so far. Its easy to add one. The definition is here[1].

"mm"    1.0;        // milimeter       (internal standard length)
"m"     1000.0;     // meter
"cm"    10.0;       // centimeter
"dm"    100.0;      // decimeter
"km"    1000000.0;  // kilometer

"in"    25.4;       // inch
"fo"    304.8;      // foot
"th"    0.0254;     // thou
"yr"    914.4;      // yard

"kg"    1.0;        // kilogramm       (internal standard mass)
"g"     0.001;      // gramm
"mg"    0.000001;   // miligramm
"t"     1000.0;     // ton 

"lb"    0.45359237; // pound
"oz"    0.45359237; // ounce
"st"    6.35029318; // Stone
"cwt"   50.80234544;// hundredwights

"°"     1.0;        // degree         (internal standard angle)
"rad"   M_PI/180;   // radian         
"gon"   360.0/400.0;// gon         

"s"     1.0;        // second         (internal standard time)
"min"   60.0;       // minute
"h"     3600.0;     // hour  

"A"     1.0;        // second         (internal standard electric current)
"K"     1.0;        // second         (internal standard thermodynamic temperature)
"cd"    1.0;        // second         (internal standard luminous intensity)        
"mol"   1.0;        // second         (internal standard amount of substance)        
"mL"    1.0;        // microliter mm^3  (derived  standard volume)
"L"     1000000.0;  // Liter      dm^3