How to solve symbolic and trigonometric equations simultaneous, two unknowns
1 Ansicht (letzte 30 Tage)
Ältere Kommentare anzeigen
christina widyaningtyas
am 30 Jul. 2022
Kommentiert: christina widyaningtyas
am 16 Aug. 2022
I still try to solve this equation to obtain alpha and gamma
R = (0.034 0.097 0.049 0.08 0.33 0.12 1.08)
d is in degrees (144 115 119 80 69 52 59)
I tried this code, and substituting R (0.07) and d (-135) to check my code, it should be give alpha = 0.15 and gamma = 1.7
But still didn't work yet
%%
syms alpha gamma %R d
R = 0.07;
d = -135;
expr1 = (R)^2 == 4*alpha^2/((2*alpha^2+1)*cosh(2*gamma)+(2*alpha^2-1)*cos(2*gamma)+2*alpha*(sinh(2*gamma)-sin(2*gamma)))
expr2 = d == atan((tanh(2*alpha*tan(gamma)+1)+tan(gamma))/(tan(gamma)-tanh(gamma)+2*alpha))
sol = solve ([expr1,expr2] , [alpha, gamma])
alphaSol = sol.alpha
gammaSol = sol.gamma
%%
syms alpha gamma %R d
R = 0.07;
d = -135;
[sol_alpha, sol_gamma] = vpasolve([(R)^2 == 4*alpha^2/((2*alpha^2+1)*cosh(2*gamma)+(2*alpha^2-1)*cos(2*gamma)+2*alpha*(sinh(2*gamma)-sin(2*gamma))), d == atand((tanh(2*alpha*tan(gamma)+1)+tan(gamma))/(tan(gamma)-tanh(gamma)+2*alpha))], [alpha,gamma])
They will give error :
- Undefined function 'atand' for input arguments of type 'sym'.
- sol_alpha = Empty sym: 0-by-1 sol_gamma = Empty sym: 0-by-1
I don't know anymore how to fix it,
Maybe anyone have any idea to help me, please?
0 Kommentare
Akzeptierte Antwort
Walter Roberson
am 3 Aug. 2022
d == atand((tanh(2*alpha*tan(gamma)+1)+tan(gamma))/(tan(gamma)-tanh(gamma)+2*alpha))
take tand() of both sides of that, getting
tand(d) == ((tanh(2*alpha*tan(gamma)+1)+tan(gamma))/(tan(gamma)-tanh(gamma)+2*alpha))
0 Kommentare
Weitere Antworten (1)
Torsten
am 3 Aug. 2022
Bearbeitet: Torsten
am 3 Aug. 2022
Your equation has several solution, as already demonstrated in a previous post.
Here is one of them:
syms alpha gamma %R d
%R = [0.034 0.097 0.049 0.08 0.33 0.12 1.08];
%d = [144 115 119 80 69 52 59]
R = 0.07;
d = -135;
%for i=1:numel(R)
%[sol_alpha(i), sol_gamma(i)] = vpasolve([R(i)^2 == 4*alpha^2/((2*alpha^2+1)*cosh(2*gamma)+(2*alpha^2-1)*cos(2*gamma)+2*alpha*(sinh(2*gamma)-sin(2*gamma))), tand(d(i)) == (tanh(2*alpha*tan(gamma)+1)+tan(gamma))/(tan(gamma)-tanh(gamma)+2*alpha)], [alpha,gamma])
%end
[sol_alpha, sol_gamma] = vpasolve([R^2 == 4*alpha^2/((2*alpha^2+1)*cosh(2*gamma)+(2*alpha^2-1)*cos(2*gamma)+2*alpha*(sinh(2*gamma)-sin(2*gamma))), tand(d) == (tanh(2*alpha*tan(gamma)+1)+tan(gamma))/(tan(gamma)-tanh(gamma)+2*alpha)], [alpha,gamma])
Siehe auch
Kategorien
Mehr zu Assumptions finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!