Function generating interpolation method and apparatus

A function calculator, comprising:

• a look-up table, said look-up table outputting a first coefficient, a second coefficient, and a third coefficient in response to a first set of input bits, said first set of input bits being a subset of a whole set of input bits;
• an adder, said adder producing a result that is the sum of a first number, a second number, and a third number, said first number being derived from said first coefficient, said second number being derived from the product of said second coefficient and a first translation of a second set of input bits, said second set of input bits being a subset of said whole set of input bits, and said third number being derived from the product of said third coefficient and a curve-fit function of a second translation of a third set of input bits, said third set of input bits being a subset of said whole set of input bits wherein said second translation is the inversion of the most significant bit of said third set of input bits.

A function calculator, comprising:

• a look-up table, said look-up table outputting a first coefficient, a second coefficient, and a third coefficient in response to a first set of input bits, said first set of input bits being a subset of a whole set of input bits;
• an adder, said adder producing a result that is the sum of a first number, a second number, and a third number, said first number being derived from said first coefficient, said second number being derived from the product of said second coefficient and a first translation of a second set of input bits, said second set of input bits being a subset of said whole set of input bits, and said third number being derived from the product of said third coefficient and a curve-fit function of a second translation of a third set of input bits, said third set of input bits being a subset of said whole set of input bits wherein said first translation is the two's-complement said second set of input bits and said second translation is the inversion of the most significant bit of said third set of input bits and wherein said second set of inputs bits and said third set of inputs bits are the same bits.

A method of function generation, comprising:

• looking-up a first coefficient, a second coefficient, and a third coefficient in response to a first set of input bits, said first set of input bits being a subset of a whole set of input bits;
• adding, a first number, a second number, and a third number to produce a result that is an approximation of the result of a mathematical function being performed on said whole set of input bits, said first number being derived from said first coefficient, said second number being derived from the product of said second coefficient and a first translation of a second set of input bits, said second set of input bits being a subset of said whole set of input bits, and said third number being derived from the product of said third coefficient and a curve-fit function of a second translation of a third set of input bits, said third set of input bits being a subset of said whole set of input bits wherein said first translation is the two's-complement said second set of input bits.

A method of function generation, comprising:

• looking-up a first coefficient, a second coefficient, and a third coefficient in response to a first set of input bits, said first set of input bits being a subset of a whole set of input bits;
• adding, a first number, a second number, and a third number to produce a result that is an approximation of the result of a mathematical function being performed on said whole set of input bits, said first number being derived from said first coefficient, said second number being derived from the product of said second coefficient and a first translation of a second set of input bits, said second set of input bits being a subset of said whole set of input bits, and said third number being derived from the product of said third coefficient and a curve-fit function of a second translation of a third set of input bits, said third set of input bits being a subset of said whole set of input bits wherein said second translation is the inversion of the most significant bit of said third set of input bits.

A method of function generation, comprising:

• looking-up a first coefficient, a second coefficient, and a third coefficient in response to a first set of input bits, said first set of input bits being a subset of a whole set of input bits;
• adding, a first number, a second number, and a third number to produce a result that is an approximation of the result of a mathematical function being performed on said whole set of input bits, said first number being derived from said first coefficient, said second number being derived from the product of said second coefficient and a first translation of a second set of input bits, said second set of input bits being a subset of said whole set of input bits, and said third number being derived from the product of said third coefficient and a curve-fit function of a second translation of a third set of input bits, said third set of input bits being a subset of said whole set of input bits wherein said first translation is the two's-complement of said second set of input bits and said second translation is the inversion of the most significant bit of said third set of input bits and wherein said second set of inputs bits and said third set of inputs bits are the same bits.