1. A non-transitory computer-readable medium in which computer program instructions are stored, which instructions, when read by a computer, cause the computer to perform a method for verifying a design of a floating point computation unit, comprising the steps of: receiving a definition of a floating point operation to test, said definition comprising a first floating point operand having a first floating point input interval and a second floating point operand having a second floating point input interval, and a floating point result having a floating point output interval, said first and second floating point input intervals and said floating point output interval having respective upper and lower floating point limits; defining a first reduced interval for said first floating point operand responsively to said upper and lower floating point limits of said second floating point input interval and said floating point output interval; selecting a first machine number in said first floating point input interval; defining a second reduced interval for said second floating point operand responsively to said first machine number and to said upper and lower limits of said floating point output interval; selecting a second machine number in said second reduced interval; and testing said floating point operation in said design using said first machine number and said second machine number as said first floating point operand and said second floating point operand.