Inverting matrix, for iterative space-charge calculations.

As explained in the general note on space-charge calculations, the presence of the space-charges of the rays causes changes to the charges on the boundary elements (that is, the electrodes and their segments), which are therefore re-calculated at each iteration.

This re-calculation uses the inverse of the main matrix. This inverse is therefore calculated before the start of ray tracing. The box that appears on the screen is labelled â€˜Inverting matrix, for space-charge calculationsâ€™. The inversion process can take a long time when the number of segments is large.

If you want to use a space-charge program, CPO2DS or CPO3DS (perhaps because you want the currents to appear in the output information) but do not want to use the space-charges, then it is possible to by-pass the inversion process. This is achieved by running the data file using CPO2D or CPO3D to set up the main matrix, but then using CPO2DS or CPO3DS for the required results.