In the Simple Units environment, any verifications of valid dimensions ignore so-called Unit annotations.

In the Simple Units environment, the eval function is overloaded to evaluate an expression, taking units into account.

Every command in the Simple Units environment that needs to determine whether an expression is valid or not, does so using the Units:-TestDimensions command.

For other properties, see the global function eval.

$\mathrm{with}\left(\mathrm{Units}\left[\mathrm{Simple}\right]\right)\:$

To enter a unit in 2-D Math input, select the unit from the appropriate Units palette. If the unit you want is not there, select $\mathrm{unit}$ and then enter the unit.

When you edit a unit, double brackets appear around it.

$\mathrm{velocity}≔\mathrm{sqrt}\left(2\mathrm{Unit}\left('\mathrm{gn}'\right)\mathrm{height}\right)$

$\mathrm{velocity}≔\sqrt{2}\sqrt{\mathrm{height}}⟦\sqrt{\mathrm{gn}}⟧$

$\mathrm{eval}\left(\mathrm{velocity}\,\mathrm{height}=3\mathrm{Unit}\left('\mathrm{ft}'\right)\right)$

$\frac{\sqrt{2}\sqrt{3}\sqrt{381}\sqrt{196133}}{5000}⟦\frac{m}{s}⟧$

$\mathrm{evalf}\left(\right)$

$4.234902778⟦\frac{m}{s}⟧$

$\mathrm{eval}\left(\mathrm{velocity}\,\mathrm{height}=0.03\mathrm{Unit}\left('\mathrm{km}'\right)\right)$

$0.01732050808\sqrt{2}\sqrt{196133}\sqrt{5}⟦\frac{m}{s}⟧$

$\mathrm{evalf}\left(\right)$

$24.25693715⟦\frac{m}{s}⟧$