Solve function supports only four decimal points

Is there a way to solve a system of equations like this with double precision without rounding? The theta vector here has precision double. But unless I limit the number of decimal points to 4 or fewer, I dont get an answer.

ts = 0.002;
syms a b;
eqn1 = 2+a*ts == 1.97720865074869;   
eqn2 = -1-a*ts == -0.977208098949782;  
eqn3 = ts^2*b == 0.00103667507747696;   
%Note: solve function seems to accept only 4 decimal places. 
%The round command is to accomodate this. Has nothing to do with the math.
sol = solve([eqn1, eqn2, eqn3],[a,b]);  %solve for a and b, ts is known
aSol=double(sol.a)
bSol=double(sol.b)

If I just use double or increase the number of decimals to 5 I get : 0×1 empty double column vector.

Answer 1

[Star Strider]

I cannot run that because the ‘theta’ vector is missing.

However, the Symbolic Math Toolbox calculates in extended precision. If the results are limited to 4 decimal places, change the format setting to display more of them. Use the vpa function to change what the Symbolic Math Toolbox displays.

.

[V. Freyr Gudmundsson]

I failed at submitting a sample that would run. I have fixed that in the original post.

You will now see the problem when you run the code. It returns a struct with two 0x1 sym fields.

However, if you reduce the number of decimals down to four, it will come up with the right answer in two 1x1 sym fields.

Answer 2

[Walter Roberson]

Add the first two equations. The a*ts cancel out, leaving the equation 1 = theta1 + theta2. If that equation is not satisfied then there cannot be any solution to the system.