A program restart assisting apparatus acquires time series data of a physical amount detected in machining, detects a change point on which a machining state of the machining is changed based on the acquired data, and records the change point of the machining state as a restartable point. Then, the program restart assisting apparatus selects a restart execution point from among the recorded restartable points, with the result that an appropriate restartable point can be easily selected.

A program restart assisting apparatus acquires time series data of a physical amount detected in machining, detects a change point on which a machining state of the machining is changed based on the acquired data, and records the change point of the machining state as a restartable point. Then, the program restart assisting apparatus selects a restart execution point from among the recorded restartable points, with the result that an appropriate restartable point can be easily selected.

A numerical controller includes a neighboring point search function that moves a tool controlled by a moving axis and a rotation axis onto a machining path directed by a machining program within the range of a neighboring point distance from a current position of the tool. When searching the neighboring point, the numerical controller determines a neighboring point with consideration for both a tool center point position and a tool attitude. By employing this search method, even when a plurality of block start points are present in the neighboring point distance from the current tool position, a block start point of the block originally desired to be restarted can be determined as a neighboring point.