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&DRIFT: XT-PLOT


DATASET

Requests output of the x(t) relation to a dataset [no dataset is written by default].

Additional information on:
  
 


angle

The angle of the lines over which the drift time is minimised, measured with respect to the y-axis. The accuracy of the calculations becomes less when this angle becomes large.

[Default: 0 degrees.]


xmin

Forms together with xmax the range over which the x(t) relation is computed.

[By default the whole x-range of the drift area is taken.]


xmax

Forms together with xmin the range over which the x(t) relation is computed.

[By default the whole x-range of the drift area is taken.]


xstep

The distance between successive x points for which a corresponding minimal drift time is computed.

[By default chosen such that the step size is a reasonable number for about 20 data points.]


jump

The number of points between two accurately calculated points. The drift times for the intermediate points are obtained by interpolating the minimising drift line from the adjacent points, a procedure that is slightly less accurate than full drift line calculation.

[By default, no point is interpolated.]


itermax

The maximum number of iterations allowed.

[Default: 5.]


eps

An accuracy parameter, to be adjusted with great care.

[Default: 1E-4.]


angle_range

To save CPU time whilst gaining precision, it sometimes makes sense to explore only a limited angular range as seen from the target sense wire.

This option should be used with great caution if a magnetic field is present since the drift lines in this case normally approach the wire at a (substantial) angle.

[The default range is +90 to -90 degrees both left and right.]


PRINT-XT-RELATION

Requests a printout of the x(t) relation.

[On by default.]


PLOT-XT-RELATION

Requests a graph of the x(t) relation.

The graph usually shows 2 curves:

Both curves are interrupted if the procedure has doubts about the accuracy of a neighbouring point - markers are used if both neighbours of a reliable point are considered unreliable.

[On by default.]


SCALE

Can be used to force a vertical scale in the x(t) relation plot, e.g. when you wish to overlay several of them.
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Formatted on 0100-09-02 at 06:56.