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. To use this functionality, add an **Extra Axis **command to your graph and change the **Units** to ‘Convert’. 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 the **Position** = ‘Right’. The defined constants are entered such that **Data** is set to ‘sqft’ and **Display** is set to ‘sqm’.

Note that it’s up to you to make sure the combination of units you enter makes sense, 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^{−1}s^{−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/s^{2} |

erg | 1E-07 | cgs unit of work1 erg = 1 dynecm = 1 g·cm^{2}/s^{2} |

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 |