undefined - Maple Programming Help

undefined

Description

 • The name undefined is a reserved word in Maple that can be produced and propagated in various ways, usually as the result of attempting to carry out an operation which cannot result in a number for the given operands.
 • undefined's typically result from operations in which one or more operands are undefined, or, in the absence of a trap (see events), from invalid operations or mathematical operations for which no single numeric value can represent the result.
 • In floating-point computations, the value Float(undefined) corresponds to the IEEE arithmetic representation for Not-a-Number (NaN).
 • undefined's from different computation environments (exact, software floats, etc.) are converted to the relevant computation environment when they occur in a mixed computation.
 • The Boolean evaluation of evalb(undefined <> undefined) always returns false.
 • To test for exactly the value undefined, as opposed to any of its variants, such as Float(undefined) or undefined+I*undefined, use the test type(expr, NumericClass(undefined)).

Examples

 > $0\mathrm{\infty }$
 ${\mathrm{undefined}}$ (1)
 > $\mathrm{\infty }-\mathrm{\infty }$
 ${\mathrm{undefined}}$ (2)
 > $\mathrm{frem}\left(\mathrm{\infty },2\right)$
 ${Float}{}\left({\mathrm{undefined}}\right)$ (3)
 > $\mathrm{CopySign}\left(1,2I\right)$
 ${\mathrm{undefined}}$ (4)
 > $\mathrm{NextAfter}\left(1,2I\right)$
 ${\mathrm{undefined}}$ (5)
 > $\mathrm{evalb}\left(\mathrm{undefined}\ne \mathrm{undefined}\right)$
 ${\mathrm{false}}$ (6)