CopySign - Maple Help

CopySign

return x with the sign of y

 Calling Sequence CopySign(x, y)

Parameters

 x - numeric type y - numeric type

Description

 • The CopySign(x, y) function returns x with its sign changed to that of y. No multiplication is performed on x if its sign is changed in the result.
 • If x is real, abs(x) = CopySign(x,1) and the sign of x can be obtained by using CopySign(1,x).
 If x is undefined, CopySign(x,y) returns x and no event is signaled.
 • If y is real, CopySign maps onto complex numerics. If y is unordered with 0 but it is not a real undefined, an invalid_operation event is signaled.
 If y is a real undefined (i.e., y is undefined or Float(undefined)), CopySign(x,y) returns y*x and no event is signaled (unless a prior rule applies).
 • If symbolic data is used in the calling sequence, this function returns unevaluated.

 • The CopySign command is thread-safe as of Maple 15.
 > $\mathrm{CopySign}\left(2,-3\right)$
 ${-2}$ (1)
 > $\mathrm{CopySign}\left(3+2I,-2\right)$
 ${-3}{-}{2}{}{I}$ (2)
 > $\mathrm{CopySign}\left(2,2I\right)$
 ${\mathrm{undefined}}$ (3)
 > $\mathrm{CopySign}\left(1,x\right)$
 ${\mathrm{CopySign}}{}\left({1}{,}{x}\right)$ (4)