Ada Programming/Attributes/'Copy Sign

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Ada. Time-tested, safe and secure.
function S'Copy_Sign (Value, Sign : T)
  return T

Description[edit | edit source]

S'Copy_Sign(X, Y) is an Ada attribute where S is any floating-point type, and X and Y are any instance of that type. This attribute represents the floating point value with the magnitude of X and the sign of Y.

If the resulting value is outside the base range of S, a Constraint_Error exception is raised.

Example[edit | edit source]

X : Float :=  1.5;
Y : Float := -1.0;
Z : Float :=  1.0;
pragma Assert (Float'Copy_Sign ( X, Y) = -1.5);   -- OK
pragma Assert (Float'Copy_Sign ( X, Z) =  1.5);   -- OK
pragma Assert (Float'Copy_Sign (-X, Z) =  1.5);   -- OK
pragma Assert (Float'Copy_Sign ( Y, Z) = -1.0);   -- Wrong

See also[edit | edit source]

Wikibook[edit | edit source]

Ada Reference Manual[edit | edit source]