You can set p->convert_units to 0 or 1 (default: 0).
p->convert_units = 1;
Now you may use the function "float unit(PARAM *p, float val, int conversion);". If (p->convert_units == 0) then the original val will be returned.
val = unit(p, val, MM2INCH);
These are the available conversions. You may set p->convert_units depending on your language settings.
enum UNIT_CONVERSION
{
MM2INCH = 1,
INCH2MM ,
CM2FOOT ,
FOOT2CM ,
CM2YARD ,
YARD2CM ,
KM2MILE ,
MILE2KM ,
KM2NAUTICAL_MILE ,
NAUTICAL_MILE2KM ,
QMM2SQINCH ,
SQINCH2QMM ,
QCM2SQFOOT ,
SQFOOT2QCM ,
QM2SQYARD ,
SQYARD2QM ,
QM2ACRE ,
ACRE2QM ,
QKM2SQMILE ,
SQMILE2QKM ,
ML2TEASPOON ,
TEASPOON2ML ,
ML2TABLESPOON ,
TABLESPOON2ML ,
ML2OUNCE ,
OUNCE2ML ,
L2CUP ,
CUP2L ,
L2PINT ,
PINT2L ,
L2QUART ,
QUART2L ,
L2GALLON ,
GALLON2L ,
GR2OUNCE ,
OUNCE2GR ,
KG2POUND ,
POUND2KG ,
T2TON ,
TON2T ,
C2FAHRENHEIT ,
FAHRENHEIT2C
};