beamenergy2velocity​(EorV,val1,restmass​,val2)

A simple function that converts beam energy to velocity, or velocity to beam energy.

A simple function that converts beam energy to velocity, or the other way around (velocity to beam energy). Mass of the particle is needed.
Inputs:
Input 1: Energy [eV] or velocity [/c].
Input 2: Value: 0 -> energy 2 velocity, 1 -> velocity 2 energy.
Input 3: Particle's rest mass (m_0) in units def. by input 4.
Input 4: Value: Mass unit. 0 -> kg, 1 -> keV/c^2, 2 -> MeV/c^2.

Output: Velocity or energy.
Energy unit: eV.
Velocity unit: Fraction of speed of light.

Mass unit: kg, keV/c^2, MeV/c^2.
Rest mass example for electron: 9.108E-31 kg, 511 keV/c^2, 0.511 MeV/c^2.