Numerical controller and simulator thereof

A numerical controller for controlling a machine having two or more paths based on a machining program for a single path in which a workpiece is attached to a main axis to be rotated and in which two or more tools are moved in a radial direction of the workpiece and a direction parallel to the axis of rotation to perform cutting, the numerical controller comprising:

• a processor configured to:
• divide the machining program into cutting motion groups by using rapid motions as delimiters,
• assign the cutting motion groups to two or more respective paths corresponding to the two or more tools,
• generate path assignment information in which the assigned cutting motion groups are overlapped between a cutting motion group located earlier on the machining program and a cutting motion group located later on the machining program such that a cutting position of the two or more tools assigned to the cutting motion group located later on the machining program does not overtake a cutting position of two or more tools assigned to the cutting motion group located earlier on the machining program, and
• control the two or more tools to move along the two or more respective paths to perform cutting of the workpiece based on the path assignment information.