Can everyone help me to correct my code?

clear all; % Clear all information 
close all; % Close all windows
clc;       % Clear Screen
% ABSTRACT
% To plot a graph Radias at interfact VS tua
syms t r;
%%This is to solve a function (0.25*r.^2 - 0.1057 - 0.25*(expint(2*log(r)))) + 0.25*log(log(r)) + (0.1611((r.^2)*log(r) + r.^2 - 1)) = t;
Eq = ((0.25*r.^2) - 0.1057 - (0.25*(expint(2*log(r)))) + (0.25*log(log(r))) + (0.1611*((r.^2)*log(r) + r.^2 - 1))) - t;
rp = linspace(0.3,1,10);
tp = zeros(1,numel(tp));
for irp = 1:numel(rp)
  tp(irp) = solve(subs(Eq,'r',rp(irp)));
end
grid on
xlim([0,1])
ylim([0,5])
set(gca,'xtick',0:0.1:1);
set(gca,'ytick',1:0.5:5)
xlabel('\Theta','fontname','Palatino','fontsize',12)
ylabel('\Radias at interface','fontname','Palatino','fontsize',12)
%title('y1 (blue) = x, y2 (green) = x^2')
set(gca,'fontname','Palatino','fontsize',12) % DON'T CHANGE
set(gcf,'paperposition',[1 1 5 5])           % DON'T CHANGE
axis square

[Stephen23]

What is the problem? Do you have a question?

[pongthep poungthong]

I cannot get a graph from this code. and I don't have idea to improve it.

[pongthep poungthong]

I follow your recommendation but I didn't get a graph , I think "the Eq" is type not correctly. I don't know how to improve it. Thank you very much for your answers.

Answer 1

[Star Strider]

You have to take ‘t’ out of the ‘Eq’ equation first, then make some other changes (see relevant ‘%’ comments) add the missing plot call, plot the real, imaginary and magnitude components of ‘Eq’, and your code works:

%This is to solve a function (0.25*r.^2 - 0.1057 - 0.25*(expint(2*log(r)))) + 0.25*log(log(r)) + (0.1611((r.^2)*log(r) + r.^2 - 1)) = t;
Eq = ((0.25*r.^2) - 0.1057 - (0.25*(expint(2*log(r)))) + (0.25*log(log(r))) + (0.1611*((r.^2)*log(r) + r.^2 - 1)));
rp = linspace(0.3,1,10);
tp = zeros(1,numel(rp));                                        % Change to ‘numel(rp)’
for irp = 1:numel(rp)
  tp(irp) = vpa(subs(Eq,'r',rp(irp)));                          % Remove ‘solve’ Call
end
figure(1)
plot(rp, real(tp),'--',  rp, imag(tp),'--',  rp,abs(tp),'-')    % Plot Call
grid on
xlim([0,1])
ylim([0,5])
set(gca,'xtick',0:0.1:1);
set(gca,'ytick',1:0.5:5)
xlabel('\Theta','fontname','Palatino','fontsize',12)
ylabel('\\Radias at interface','fontname','Palatino','fontsize',12)
%title('y1 (blue) = x, y2 (green) = x^2')
set(gca,'fontname','Palatino','fontsize',12) % DON'T CHANGE
set(gcf,'paperposition',[1 1 5 5])           % DON'T CHANGE
axis square
legend('Re\{Eq\}', 'Im\{Eq\}', '|Eq|')

EDIT — Added real, imaginary, and absolute values of ‘Eq’ to the plot and legend calls.

Answer 2

[Thorsten]

There is no plot command

plot(rp, tp)

[pongthep poungthong]

I knew that but I think my code is wrong and I cannot find them.

[pongthep poungthong]

I think "0.25*(expint(2*log(r))))" in Eq is not correct . What does it change to?.