Units

Incorrect use of Units can result in all sorts of problems e.g. the mixing of Imperial and Metric units even led to destruction of NASA’s Mars Climate Orbiter.  Thus, it is necessary to manage units reliably and effectively.

The j2 Universal Tool-Kit presents a unique solution to this problem.  All data is stored in the International System of Units (SI) values and all calculations use SI values.   This avoids the use of “magic numbers” in equations to accommodate a mix of units.  However, people do work in different units and it is helpful for them to be able to present their information in a format that is preferred or familiar.  Thus, it is possible to change the scaling of a value that is entered and viewed by changing the units.

This can be achieved quickly and easily by simply selecting the desired units in the Units Window.

By changing the values in the units window, what is displayed is re-scaled.

These changes are not simply switching between Metric (SI)and Imperial units, but the units logic built in to the j2 Universal Framework can then enable units to be mixed and matched.

Units can be changed as often as desired providing ultimate flexibility without confusion, so dimensions can be displayed in mm but altitude in ft.

The same is true when entering data.  Defining the breakpoints can be made in degrees.

However, the derivative is per radian, so the units can be changed into radians and the derivative value entered.  Everything is automatically recalculated without transcription or conversion errors creeping in.

Users are able to add additional unit types and scales into the system if necessary.  For consistent team working such additions become available to everyone on the network.