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+--- Thread: HP 41 Polar Plots? (/thread-195.html)
HP 41 Polar Plots? - mbrethen - 12-21-2013 08:41 PM
Anyone know if it's possible to plot f(r,theta) using an hp 41 and 82240 printer? For example:
R(theta) = 1/2 + 3/4*sin^2(theta) + 1/2*cos(theta)
describes the approximate plastic zone shape (normalized) ahead of a crack tip. Below is the solution in r, theta, x, y from 0< theta < 180 deg.
Code:
R θ x y
1.00E+00 0 1.00E+00 0.00E+00
1.03E+00 15 9.98E-01 2.67E-01
1.12E+00 30 9.70E-01 5.60E-01
1.23E+00 45 8.69E-01 8.69E-01
1.31E+00 60 6.56E-01 1.14E+00
1.33E+00 75 3.44E-01 1.28E+00
1.25E+00 90 7.66E-17 1.25E+00
1.07E+00 105 -2.77E-01 1.03E+00
8.13E-01 120 -4.06E-01 7.04E-01
5.21E-01 135 -3.69E-01 3.69E-01
2.54E-01 150 -2.20E-01 1.27E-01
6.73E-02 165 -6.50E-02 1.74E-02
0.00E+00 180 0.00E+00 0.00E+00Ideally, you'd sort the x, y values to get the correct shape. I thought about writing a subroutine to do this using either "regplot" or "stkplot". Note there a two solutions at x = 0.
RE: HP 41 Polar Plots? - SlideRule - 12-21-2013 11:08 PM
mbrethern
Someplace to start...
Polar Plot
...with an HP67-97 article/program from Electronics 1979
HP-67/97 program plots antenna's polar pattern
BEST!
SlideRule
RE: HP 41 Polar Plots? - Ángel Martin - 12-22-2013 08:12 AM
If you're game for digging old software a few articles in PPC journal on related topics may help:
V10N6p23
V11N5p12
V11N7p10
V12N3p36
V13N5p20
V14N5p29