HISTOGRAM CALCULATION SYSTEM, ELECTRONIC TESTING DEVICE AND HISTOGRAM CALCULATING METHOD

摘要

PROBLEM TO BE SOLVED: To make a histogram calculation having a bin of exponential spacing temporally/spatially efficient. SOLUTION: A system (101) for calculating a histogram having a bin of exponential spacing has a base 2 logarithm estimator (120) configured so as to generate an approximate base 2 logarithm (170) of floating point display (160, 165) of a data sample. The system (101) has further an approximate histogram bin computer (130) configured so as to calculate an approximate histogram bin number (175) that relates to the approximate base 2 logarithm (170), and a histogram bin regulator (140) configured so as to obtain an accurate histogram bin number (180) by adjusting the approximate histogram bin number (175) on the basis of comparison between a data value representing an approximate histogram bin number and a data sample. COPYRIGHT: (C)2004,JPO