Conversion Factors
DataGraph has over 100 defined constants that can be used to convert axis values from one unit of measure to another, without you having to enter any conversion factors. They include length, area, volume, time, and more.
These constants are used in the unit conversion in the Extra Axis command. Add an Extra Axis command to your graph and change the Units to ‘Convert’ to use this functionality. Then you will have two new entry boxes named Data and Display.
One use case for this functionality is to provide two units of measure for a set of data. For example, below we are graphing data in feet square, but we also want to show meters square on the right.
To create this graph, the Extra Axis options are Units = ‘Convert’ and Position = ‘Right’. The defined constants are entered such that Data is set to ‘sqft’ and Display is set to ‘sqm’.
Some of the constants have more than one symbol defined. For example, a gallon can be understood as ‘gal’, ‘gallon’, or ‘gallons’. If you enter a symbol that is not defined a warning will be displayed that lists all of the symbolic constants that have been defined.
You can think of each of these constants as built-in variables that represent a conversion factor based on SI units. For example, the value for meters ‘m’ is one since meters are the SI unit for length. The value for ‘cm’ is 0.01 since cm is one-one hundredth of the meter. The data conversion is done by multiplying by the ratio of Data/Display to show the requested units.
Note: DataGraph will not warn you if you pick a combination of units that don’t make physical sense (i.e., converting from volume to mass), so always double-check! A list of all the defined constants is provided below.
| key | value | Description |
| A | 1 | Current |
| acre, acres | 4046.8564224 | Area |
| atm | 101325 | Pressure (standard atmosphere) |
| Å,å | 1E-10 | Length |
| at | 98066.5 | Pressure (technical atmosphere) |
| bar, bars | 1E+05 | Pressure |
| barye | 0.1 | Pressure 1 barye = 0.1 Pa = 1 g·cm−1s−2 |
| biot,biots | 3.33564E-10 | Electromagnetic (cgs units) |
| BTU | 1054.615 | Work, British thermal unit |
| C, coulomb, coulombs | 1 | SI unit of electric charge, A*sec |
| centimeter, centimeters, centimetre | 0.01 | Length |
| cfs | 0.028316846592 | cubic feet per second |
| cm | 0.01 | centimeter |
| cuft | 0.028316846592 | cubic feet |
| cuin | 1.6387064E-05 | cubic inches |
| cukm | 1E+09 | cubic kilometers |
| cum | 1 | cubic meters |
| cumiles | 4168181825.44058 | Volume, cubic miles |
| cuyd | 0.764554857984 | volume, cubic yards |
| cwt | 45.359237 | hundredweight |
| day, days | 86400 | in seconds |
| deg, degree, degrees | 0.0174532925199433 | Angle in radians |
| dyn,dyne | 1E-05 | cgs unit of force1 dyne = 1 g·cm/s2 |
| erg | 1E-07 | cgs unit of work1 erg = 1 dynecm = 1 g·cm2/s2 |
| feet, ft, foot | 0.3048 | Length |
| floz | 2.957353E-05 | Volume |
| fm | 1E-15 | femtometer |
| furlong | 201.168 | Length |
| g, gr, gram, grams | 0.001 | Mass |
| gal, gallon, gallons | 0.003785411784 | Volume |
| G, gauss | 0.0001 | Gauss, strength of magnetic field |
| grain, grains | 6.479891E-05 | Mass |
| h, hr, hour, hours | 3600 | in seconds |
| H | 1 | henry, SI unit of electrical inductance |
| hectare, hectares | 10000 | area |
| hp | 745.6998715822702 | Horsepower |
| imperialgallon, imperialgallons | 0.00454609 | Volume |
| in,inch,inches | 0.0254 | Length |
| J | 1 | Joule |
| kayser, kaysers | 100 | wavenumber, formerly called the kayser |
| kg, kilo, kilos, kilogram, kilograms | 1 | Mass |
| mph | 0.2777777… | Length/Time |
| kip,kips | 4448.2216 | Imperial unit of force |
| km | 1000 | Length, kilometers |
| kN | 1000 | kiloNewtons |
| knot,knots | 0.514434666… | Length/Time |
| kPa | 1000 | kiloPascals |
| kW | 1000 | kiloWatt |
| L, l, liter, liters, litre | 0.001 | Volume |
| lb,lbs | 0.45359237 | Weight |
| league, leagues | 4828.032 | Length |
| mach,Mach | 340.4014189333333 | Length/Time |
| mA, ms, mV, mW, mΩ | 0.001 | 1/thousand of an SI unit |
| maxwell | 1E-07 | derived CGS unit of magnetic flux |
| m, meters, meter, metre | 1 | Length, meter |
| mg | 1E-06 | milligram |
| mi,mile,miles | 1609.344 | Length |
| min, minute, minutes | 60 | Time |
| ml | 1E-06 | Volume |
| mm | 0.001 | Length, millimeter |
| MMBtu, mmBTU | 1054615000 | One million British Thermal Units (BTU) |
| mmHg | 133.322 | Pressure |
| N_A | 6.02214085774E+23 | Avogadro’s Number |
| MPa | 10^6 | Pressure |
| mph | 0.44704 | speed |
| nA,nm,ns,nV,nΩ | 1E-09 | 1/billionth of SI unit |
| N | 1 | Newtons |
| Oe, oersted | 79.577 | Auxiliary magnetic field Hin the CGSunits |
| oz | 0.0283493 | Weight |
| Pa | 1 | Pressure, SI unit, Pascal |
| pdl | 0.138255 | Force, English units, poundal |
| pt, pint, pints | 0.0004731 | Volume |
| pm, pV, pΩ | 1E-12 | pico conversion |
| poise | 0.1 | dynamic viscosity cgs units |
| pound,pounds | 0.4535888 | Weight |
| psi | 6894.76 | Pressure |
| quart | 0.000946352946 | Volume |
| s, sec, second, seconds | 1 | Time |
| sqft | 0.09290304 | Area, square feet |
| sqkm | 10^6 | Area, square kilometers |
| sqm | 1 | Area, square meters |
| sqmile, sqmiles | 2589988.110336 | Area, square miles |
| sqyd | 0.836127 | Area, square yards |
| statC, statcoulomb, esu, Fr | 3.33564E-10 | cgs, electrostatic unit of charge |
| statH | 898800000000 | unit of inductance in cgs |
| statV, statvolt,, statvolts | 299.792458 | Unit of electromotive force (EMF) or potential difference in cgs |
| stone,stones | 6.3502432 | Weight, English units |
| T | 1 | Tesla, strength of magnetic field |
| torr | 133.322 | pressure |
| ukfloz | 2.8413E-05 | UK Fluid Ounces |
| ukgal, ukgals, ukgallon | 0.00454608 | UK Gallon |
| ukpint, ukpints, ukpt | 0.00056826 | UK Pint |
| ukquart | 0.001136 | UK quart |
| V | 1 | Volt, derived SI unit for electric potential |
| W | 1 | Watt |
| Wb,weber | 1 | SI unit of magnetic flux |
| week, weeks | 604800 | time |
| yard,yards,yd | 0.9144 | Length |
| º | 0.0174532925199433 | 1 degree in radians |
| µA,µg,µm,µs,µV,µW,µΩ | 1E-06 | micro conversion |
| Ω | 1 | Electrical resistance, Ohm |