defining symbolic piecewise function

Good evening, I have an issue trying to define a piecewise symbolic function in matlab.

I already tried using the piecewise predefined function as shown in the next piece of code:

    a = sym('a'); l = sym('l');
    r_i = symfun(r_c(a) + r_1, a); l_i = symfun((pi/2)*r_c(a), a); l_2 = symfun(l_i(a) + r_2 - r_i(a), a);
    r = symfun(piecewise((0 <= l) && (l < l_i(a)),...
        r_1 + r_c(a) * (1 - cos(l / r_c(a))),...
        (l_i(a)<=l) && (l<l_2(a)),...
        r_i(a) + l - (pi/2) * r_c(a)),...
        [l, a]);

but it shows this error "Conversion to logical from sym is not possible.".

I guess it is because I can not use a symbolic function in the chain of inequalities, but I do not know how to fix this, so please could anyone help me? Thankyou very much and merry Christmas!!

PS

This piece of code is contained in a function.m file.

[Ramnarayan Krishnamurthy]

The following link may be useful:

https://www.mathworks.com/matlabcentral/answers/69143-conversion-to-logical-from-sym-is-not-possible-error-shows-up-when-i-try-to-execute-the-following

Answer 1

[Francesco Collini]

I found out that the solution for this problem is:

a = sym('a'); l = sym('l');
    r_i = symfun(r_c(a) + r_1, a); l_i = symfun((pi/2)*r_c(a), a); l_2 = symfun(l_i(a) + r_2 - r_i(a), a);
    r = symfun(piecewise((0 <= l) & (l < l_i(a)),...
        r_1 + r_c(a) * (1 - cos(l / r_c(a))),...
        (l_i(a)<=l) & (l<l_2(a)),...
        r_i(a) + l - (pi/2) * r_c(a)),...
        [l, a]);
    

The problem was in the definition of the intervals, where a single character "&" must be used instead two "&&" to define an interval under more than one condition.