Question:

Is there a way to write the RA command so that the necessary angles
are automatically correct to avoid the error message "need closer
angles"?

Answer:

"Need closer angles" occurs when area under the righting arm curve is
being calculated and there is a relatively narrow peak which is not
well represented by the angles given.  The MAXVCG solving process
automatically includes more angles if necessary, but the RA command
does not.  As you probably know already, you can avoid this problem
by using a suitably small angle increment in the range of angles
where the peak occurs.  For example, in a damaged stability case, the
range of stability may be small and therefore closer angles will be
required.  For example,

   SOLVE
   ANGLES = 0, 2 
   ANGELS *
   RA /LIM

If you give a short list of angles such as this, RA will
automatically extend it as far as necessary using the last increment
(2° in this case).  This avoids going beyond the range necessary to
satisfy the angles involved in the LIMITs.

You can also vary the angle increment.  For example,

   ANGLES = 0, 5, ..., 20, 22.5, ... 30, 35, ... 60

results in 5 degree increments from 0 to 60 except between 20 and 30
where the increment is 2.5 degrees.


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