The verify(expr1, expr2, boolean) and verify(expr1, expr2, truefalse) calling sequences perform an evalb comparison. That is, verify(a, b, boolean) = evalb(a = b) and verify(a, b, truefalse) = evalb(a = b).

If a verification ver is given, then boolean acts as a filter, converting anything returned by verify into either true, false, or FAIL.

The verification truefalse makes one further change, converting any FAIL results into false.

These are useful in case the result from verify is to be used as input to another procedure such as sort or select.

The verifications boolean and truefalse are symmetric and a verification boolean(ver) is symmetric if and only if the verification ver is symmetric. If a verification ver is symmetric, then this implies that the verification truefalse(ver) is symmetric.

$\mathrm{evalb}\left(\left[\mathrm{undefined}\right]=\left[\mathrm{undefined}\right]\right)$

$\mathrm{true}$

$\mathrm{verify}\left(\left[\mathrm{undefined}\right]\,\left[\mathrm{undefined}\right]\,'\mathrm{boolean}'\right)$

$\mathrm{true}$

$\mathrm{verify}\left(\left[\mathrm{undefined}\right]\,\left[\mathrm{undefined}\right]\,'\mathrm{list}'\right)$

$\mathrm{true}$

$\mathrm{verify}\left({\left(x-1\right)}^2\,x^2-2x+1\,'\mathrm{boolean}'\right)$

$\mathrm{false}$

$\mathrm{verify}\left(\left[3\right]\,3\,'\mathrm{list}'\right)$

$\mathrm{false}$

$\mathrm{verify}\left(\left[3\right]\,3\,'\mathrm{boolean}\left(\mathrm{list}\right)'\right)$

$\mathrm{false}$

$\mathrm{verify}\left(0.3232\,0.3233\,'\mathrm{float}\left(1\right)'\right)$

$\left[\mathrm{false}\,1.\times {10}^6\,\mathrm{ulps}\right]$

$\mathrm{verify}\left(0.3232\,0.3233\,'\mathrm{boolean}\left(\mathrm{float}\left(1\right)\right)'\right)$

$\mathrm{false}$

$\mathrm{verify}\left(\sin \left(x\right)\,0\,\mathrm{greater\_than}\right)$

$\mathrm{FAIL}$

$\mathrm{verify}\left(\sin \left(x\right)\,0\,\mathrm{boolean}\left(\mathrm{greater\_than}\right)\right)$

$\mathrm{FAIL}$

$\mathrm{verify}\left(\sin \left(x\right)\,0\,\mathrm{truefalse}\left(\mathrm{greater\_than}\right)\right)$

$\mathrm{false}$

$\mathrm{map}\left(\mathrm{verify}\,\left[3\,5\,a\,b\,\exp \left(1\right)\,\exp \left(2\right)\right]\,\mathrm{\pi }\,\mathrm{less\_than}\right)$

$\left[\mathrm{true}\,\mathrm{false}\,\mathrm{FAIL}\,\mathrm{FAIL}\,\mathrm{true}\,\mathrm{false}\right]$

$\mathrm{map}\left(\mathrm{verify}\,\left[3\,5\,a\,b\,\exp \left(1\right)\,\exp \left(2\right)\right]\,\mathrm{\pi }\,\mathrm{truefalse}\left(\mathrm{less\_than}\right)\right)$

$\left[\mathrm{true}\,\mathrm{false}\,\mathrm{false}\,\mathrm{false}\,\mathrm{true}\,\mathrm{false}\right]$