How to fix this error:"Input arguments must be convertible to floating-point numbers."

I want to use the maximum value to solve R, but I don't know how to fix the error.

clc; clear all; close all;
syms R

step = 10^-12;
t = [-1*10^-8 : step : 1*10^-7];
A=12;

%R = 2.66e-3;
L = 0.406e-9;
C = 1.716e-9;

a = R/(2*L);
n = 1/(sqrt(L*C));
d = sqrt(((n)^2)-(a^2));

T = 15*10^-9 ; % + sqrt(L.*C)%;
m = A/T;
tow = R*C;
     
unitstep_1 = t>=0;
unitstep_2 = (t-T)>=0;
     
Vct_t = unitstep_1.*( t - (2.*a./n^2) + (exp(-a.*t)./d).*(( (2.*a./n).*sin(d.*t + atan(d./a))) - sin(d.*t) ));
    
Vct_T = unitstep_2.*( (t-T) - (2.*a./n^2) + (exp(-a.*(t-T))./d).*(( (2.*a./n).*sin(d.*(t-T) + atan(d./a))) - sin(d.*(t-T)) ));

Vc = m.*(Vct_t - Vct_T);
Vmax = max(Vc);

ANS = solve( round(Vmax,2) == 13.10 )

[CHUNYI YEH]

the error messages are:

Error using sym/max (line 123)

Input arguments must be convertible to floating-point numbers.

Error in solve_with_delay_RC_all (line 28)

Vmax = max(Vc);

[Steven Lord]

What should this return? Is x greater than y, less than y, equal to y, or can we not determine their ordering?

syms x y
M = max(x, y)

Error using symengine
Input arguments must be convertible to floating-point numbers.

Error in sym/privBinaryOp (line 1034)
Csym = mupadmex(op,args{1}.s, args{2}.s, varargin{:});

Error in sym/max (line 108)
C = privBinaryOp(X, Y, 'symobj::zipWithImplicitExpansion', 'symobj::maxComplex', nanflag);

[CHUNYI YEH]

Oh, I think it’s not determine. But how to avoid this problem if I need the maximum value? Use for loop to change R and find the maximum value which is equal to my setting?But I think it’s not the best solution...😂 Thank you

Answer 1

[Gaurav Garg]

Hi Chunyi,

I ran the code as it is, and couldn't reproduce the issue.

[CHUNYI YEH]

Hello, Gautama, thanks for the information. Maybe I will ran again in my lab’s computer, but I don’t think it’s the version problem.🤔