motorclass.m

来自「航天工程工具箱」· M 代码 · 共 26 行

function y=motorclass(m)
%MOTORCLASS  Display motor class or impulse.
%   Y = MOTORCLASS(M) where M can be either the rocket-motor's
%   motor class or its total impulse.
%   If it is a class (a letter ranging from 'A' to 'Z', string 'A/2' or 'A/4')
%   it will return the interval of total impulse for this class.
%   Reversely if M is the motors total impulse, then it will return
%   the class for this motor.
%
%   See also LOADENG, SAVEENG, PLOTENG.

% Copyright (c) 2002-02-09, B. Rasmus Anthin.
% Revision 2003-07-21.

if ischar(m)
   m=upper(m);
   if strcmp(m,'A/2'),m=char(64);end
   if strcmp(m,'A/4'),m=char(63);end
   y=2.5*2^(m-'A');
   y=[y/2 y];
else
   y=char(ceil(log(m/2.5)/log(2))+'A');
   if y==64,y='A/2';end
   if y==63,y='A/4';end
end