3D curvature information.

 

For the benefit of users who are editing or constructing an 'input data file' without the use of the data-builder (that is, pre-processor), curvature information can be re-used. This can be useful when a large number of electrodes have the same centre of curvature or the same axis.

 

The data-builder (that is, pre-processor) does not include this option.

 

Before May 1998 a line of the type:

0 n address of curvature information

had to be included in the data file.

 

After May 1998 this line is not needed. If the data-builder is used it must be omitted. If the data-builder is not used it can be present, in which case it is read by the program and the information is used, to retain compatibility with older data files.

 

Users who want to enter information on a large number of curved electrodes (eg for a multi-cylinder lens) and who want to minimise the number of lines of data should read on.

 

Sometimes two or more electrodes (or part electrodes) can share the same curvature (eg they might lie on the same cylindrical surface), so this line is present to make such sharing possible. For a sphere, cylinder or cone, enter an integer to denote an 'address' for retaining the curvature information. For other curved electrodes or segments (that is, str, cre, est, ect, edt, but not ctr), enter the letter 'y' or 'n' (for 'yes' or 'no' in answer to the question 'has the curvature information been read-in before'), and follow this with an integer to denote an 'address'. The curved segment ctr is an exception (for technical reasons) and so the letter 'n' must always be entered for this type of segment. If 'n' is entered, then all the required curvature information must be entered on the following lines (and this information will be retained at the specified address, for possible later use if the segments are further subdivided).

 

If you do not want to keep track of the addresses, and if the curvature of an electrode is definitely not going to be re-used, then simply put 0 for the address (and the program will then assign a unique address, counting down from the highest allowed address, 'maxvolts'. Otherwise the address must be different from the curvature address of any other electrode or segment that has a different curvature, and must lie in the range 1 to 'maxvolts'.

But if later triangles or rectangles have the same curvature information (i.e. are on same surface) then, if a certain condition is satisfied (see below), only the address need be given, not the detailed information. Also, the curvature address of a single triangle or rectangle can, if the same condition is satisfied, be the same as that of a previously entered whole electrode that has the same curvature. The condition is that the inscribing correction has not been used (see the detailed note and the general note on inscribing).