Operation circuit

Patent Granted PROBLEM TO BE SOLVED: To attain high speed operation while reducing the circuit scale. ; SOLUTION: An operation circuit for determining an approximation straight line by a method of least square using a plurality of sample data comprises a means for decimating predetermined data from sample data stored in a memory 3, an operating section 4 for determining an approximation straight line by a method of least square using decimated data, and an operating means 7 for approximating the denominator of division operation in the operating section 4 to the power of 2.