const for degrees to radians, pi/180

Result of rotation for 2 seismograms.

Rotates the given seismograms from their given azimuths so the output radial is along the new azimuth and the output transverse is perpendicular to it.

creates a new Seismogram where the value at each sample is the vector magnitude of the 3 corresponding data points from each seismogram. Each of the 3 seismograms are assumed to be mutually perpendicular so that each set of samples gives a vector in 3-dimensional space. In particular all three seismograms must have the same number of samples and sample rate. It is assumed, but not checked, that they will be the three components of motion at a station (ie matching network, station and location codes) and have the same start time.