The objective of the present invention is to provide a sphygmomanometer that is easy to use. In one embodiment, a boundary value problem solver is used to guide the munition from one configuration to another configuration at a different altitude using a waypoint-based search tree where a number of leaves grows linearly with the depth of the tree. in-phase signals are sampled twice a symbol at the in-phase symbol sampling time and at the quadrature-phase symbol sampling time. Each node is moved according to a specific smoothing algorithm so as to keep element included angles, skew and distortion to a minimum. A memory may store the pulse number for the closest certain position and the certain number of pulses or information from which these are induced is provided. The present invention is devised so that if a first storage device is updated by writing data into this first storage device, the update data relating to the updating of the first storage device is written into a second storage device.