In a magnetic resonance apparatus having an RF radiating coil and gradient
coils, and in a method for operating such a magnetic resonance apparatus,
a pulse sequence, composed of multiple time steps, is specified for
operating the gradient coils to time-dependently select regions of a
selected slice of a selected volume of a subject. A non-linear equation
system is then solved to obtain feed parameters for individual channels
of the transmit coil for each time step, with specification of a desired
target magnetization, and dependent on the pulse sequence specified for
the gradient coils. The non-linear equation system is based on discrete
values for time and space variable and, in addition to equations
resulting from the Bloch equation, which are non-linear in their feed
parameters, includes at least one additional equation that describes
boundary conditions for the examination of the subject.