GHS FAQ

Question QA035 :
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 degrees 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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