equation system returns Empty sym: 0-by-1

hi,
while solving a system of equations all the solutions appear as Empty sym: 0-by-1.
how do i solve this?

1 commentaire

x0=0
x1=0.25
x2=0.5
x3=0.75
x4=1
x5=1.25
x6=1.5
x7=1.75
x8=2
x9=2.25
x10=2.5
x11=2.75
x12=3
y0=0.652
y1=0.217
y2=0.264
y3=0.0689
y4=-0.183
y5=0.209
y6=0.529
y7=0.689
y8=1.18
y9=1.48
y10=2.21
y11=3.09
y12=3.64
syms a b c d e f g h i j k l
eqn1 = a+b*x0+c*(x0^3)+d*(x0^4)+e*(x0^5)+f*(x0^6)+g*(x0^7)+h*(x0^8)+i*(x0^9)+j*(x0^10)+k*(x0^11)+l*(x0^12) == y0;
eqn2 = a+b*x1+c*(x1^3)+d*(x1^4)+e*(x1^5)+f*(x1^6)+g*(x1^7)+h*(x1^8)+i*(x1^9)+j*(x1^10)+k*(x1^11)+l*(x1^12) == y1;
eqn3 = a+b*x2+c*(x2^3)+d*(x2^4)+e*(x2^5)+f*(x2^6)+g*(x2^7)+h*(x2^8)+i*(x2^9)+j*(x2^10)+k*(x2^11)+l*(x2^12) == y2;
eqn4 = a+b*x3+c*(x3^3)+d*(x3^4)+e*(x3^5)+f*(x3^6)+g*(x3^7)+h*(x3^8)+i*(x3^9)+j*(x3^10)+k*(x3^11)+l*(x3^12) == y3;
eqn5 = a+b*x4+c*(x4^3)+d*(x4^4)+e*(x4^5)+f*(x4^6)+g*(x4^7)+h*(x4^8)+i*(x4^9)+j*(x4^10)+k*(x4^11)+l*(x4^12) == y4;
eqn6 = a+b*x5+c*(x5^3)+d*(x5^4)+e*(x5^5)+f*(x5^6)+g*(x5^7)+h*(x5^8)+i*(x5^9)+j*(x5^10)+k*(x5^11)+l*(x5^12) == y5;
eqn7 = a+b*x6+c*(x6^3)+d*(x6^4)+e*(x6^5)+f*(x6^6)+g*(x6^7)+h*(x6^8)+i*(x6^9)+j*(x6^10)+k*(x6^11)+l*(x6^12) == y6;
eqn8 = a+b*x7+c*(x7^3)+d*(x7^4)+e*(x7^5)+f*(x7^6)+g*(x7^7)+h*(x7^8)+i*(x7^9)+j*(x7^10)+k*(x7^11)+l*(x7^12) == y7;
eqn9 = a+b*x8+c*(x8^3)+d*(x8^4)+e*(x8^5)+f*(x8^6)+g*(x8^7)+h*(x8^8)+i*(x8^9)+j*(x8^10)+k*(x8^11)+l*(x8^12) == y8;
eqn10 = a+b*x9+c*(x9^3)+d*(x9^4)+e*(x9^5)+f*(x9^6)+g*(x9^7)+h*(x9^8)+i*(x9^9)+j*(x9^10)+k*(x9^11)+l*(x9^12) == y9;
eqn11 = a+b*x10+c*(x10^3)+d*(x10^4)+e*(x10^5)+f*(x10^6)+g*(x10^7)+h*(x10^8)+i*(x10^9)+j*(x10^10)+k*(x10^11)+l*(x10^12) == y10;
eqn12 = a+b*x11+c*(x11^3)+d*(x11^4)+e*(x11^5)+f*(x11^6)+g*(x11^7)+h*(x11^8)+i*(x11^9)+j*(x11^10)+k*(x11^11)+l*(x11^12) == y11;
eqn13 = a+b*x12+c*(x12^3)+d*(x12^4)+e*(x12^5)+f*(x12^6)+g*(x12^7)+h*(x12^8)+i*(x12^9)+j*(x12^10)+k*(x12^11)+l*(x12^12) == y12;
sol = solve([eqn1, eqn2, eqn3, eqn4, eqn5, eqn6, eqn7, eqn8, eqn9, eqn10, eqn11, eqn12, eqn13], [a, b, c, d, e, f, g, h, i, j, k, l]);
aSol = sol.a
bSol = sol.b
cSol = sol.c
dSol = sol.d
eSol = sol.e
fSol = sol.f
gSol = sol.g
hSol = sol.h
iSol = sol.i
jSol = sol.j
kSol = sol.k
lSol = sol.l

Connectez-vous pour commenter.

Réponses (1)

Walter Roberson
Walter Roberson le 21 Déc 2020
Modifié(e) : Walter Roberson le 21 Déc 2020

0 votes

you have 13 linear equations in 12 variables. No solution would be expected.
You could be using \ to solve this if there were a solution.

Catégories

En savoir plus sur Language Fundamentals dans Centre d'aide et File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by