• Raymond Toy's avatar
    Increase accuracy of tan near multiples of pi/4. · b71b7c85
    Raymond Toy authored
    code/irrat-dd.lisp
    o Make REDUCE-ARG return an extra result.  Since the reduction returns
      3 double's, return a double-double result and the third double
      result for extra accuracy
    o Update dd-%tan and dd-%%tan to take the extra arg.
    o Add new constant dd-pi/4-lo.
    o Increase accuracy of tan by using the relationship
      tan(pi/4-y)=(1-tan(y))/(1+tan(y)).
    
    tests/trig.lisp:
    o Update the allowed error threshold for two tests to reflect the
      increased accuracy.
    b71b7c85
trig.lisp 13.4 KB