Trigonometric Functions for the HP-38C/HP-12C

[bshoring]

[quote='Gerson W. Barbosa' pid='52957' dateline='1459028300']

My results on RPN-38 CX, using the original constants are below, after yours, Gerson. In a few instances the longer constants produced different results, which I've shown where there was a difference.

0.9999 GTO 35 R/S --> 89.18960866 ; asin(0.9999)
89.18970856 (mine)
0.9999 GTO 44 R/S --> 0.8102914371 ; acos(0.9999)
same for mine
0.9999 GTO 50 R/S --> 44.99713507 ; atan(0.9999)
same for mine

Other examples:

cos(0.01) = 0.9999999848 same for mine
sin(0.01) = 1.745329243E-04 same for mine
tan(0.01) = 1.745329270E-04 same for mine

cos(30) = 0.8660254038 I got 0.8660254008
sin(30) = 0.5000000000 I got 0.5000000005
tan(30) = 0.5773502692 I got 0.5773502771


cos(60) = 0.500000000(1) I got 0.499999311
sin(60) = 0.866025403(7) I got 0.866025801
tan(60) = 1.73205080(8) I got 1.732053989

sin(89.99) = 0.9999999848 I got 0.999999987
cos(89.99) = 1.7453(37879)E-4 I got 1.597989268E-4 (1.597989379E-4 with longer constants)
tan(89.99) = 5729.5(49544) I got 6257.864226

sin(89.9999) = 1.000000000 I got same
cos(89.9999) = 1.7462(35540)E-6 I got 1.300050952E-5 (1.300049244E-5 with longer constants)
tan(89.9999) = 572(660.4329) I got 76920.06211

asin(0) = 0.000000000 I got same
acos(0) = Error 0 I got same
atan(0) = 0.000000000 I got same

asin(1e-10) = 90.00000000 I got ZERO for asin, 90 for acos

atan(0.4142135624) = 22.50000000 I got same

atan(1) = 45.00000000 I got same

acos(0.8660254038) = 30.00000000 I got same

atan(50) = 88.85423716 I got same

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Forensic result:

9 R/S x<>y R/S R/S / GTO 50 R/S GTO 44 R/S GTO 35 R/S --> 9.000000272
I got same with original constants. But after adding the longer constants in R0 & R6, I get 9.000000282
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