Information processing apparatus, and recording medium storing computer program

A recording medium storing a program that upon execution by a computer causes the computer to function as an information processing apparatus for supplying a rotational angle of a moving object to a controller of the moving object, the information processing apparatus comprising:

• an acquisition unit configured to acquire a first phase signal and a second phase signal that are acquired by an encoder measuring a rotation of the moving object;
• and
• a calculation unit configured to calculate the rotational angle of the moving object by an iterative calculation so as to satisfy a relational expression bearing an arctangent, the relational expression bearing the arctangent using addition or subtraction including a first cosine wave and a second cosine wave at a higher harmonic of the first cosine wave for the first phase signal, and addition or subtraction including a first sine wave and a second sine wave at a higher harmonic of the first sine wave for the second phase signal.