Information processing apparatus and information processing method

An information processing apparatus comprising:

• sensor data acquisition circuitry to acquire measurement values of a physical quantity of a mechanical apparatus measured by a sensor, and acquire, as sensor data, measurement values from a first time point to an N-th time point (N is an integer of two or more) among the measurement values;
• internal variable holding circuitry to hold a smaller number of values of an internal variable than the N, the internal variable being sequentially calculated in time series based on the sensor data;
• internal variable calculation circuitry to calculate the internal variable corresponding to a (j+1)-th time point (j is an integer of one to N−1) based on the sensor data at the (j+1)-th time point and the internal variable corresponding to a j-th time point;
• feature calculation circuitry to calculate a feature by extracting a statistical characteristic included in the sensor data from the first time point to the N-th time point based on the internal variable at the N-th time point;
• and
• state diagnosis circuitry to make a diagnosis of a state of the mechanical apparatus based on the feature.