%% programa presion PAUTA

clear all;
close all;
clc ;

%% datos inciales
L = 1;          %longitud de la cuerda
A = 1;        %amplitud
c = 1;          %velocidad de propagacion de ondas
x = 0:L/10000:L;  %vector de distancia
Nx = length(x); %longitud de vector x

%% ciclo principal de animacion

N = 500;          %numero de terminos de la sumatoria

pxt(1:Nx) = 0;   %incializacion de presion

for t = 0:0.01:5.45
    
    pxt(1:Nx) = 0;   %incializacion de presion
    
    for n = 1:N
        
        kn(n) = ( (2*n -1)*pi )/(2*L);
        wn(n) = c*kn(n);
        
        An(n) = (-2*A)/((2*n-1)*pi)*cos((2*n-1)*7*pi/16);
        Bn(n) = (4*A*L)/((2*n-1)^2*pi^2*c)*(1-cos((2*n-1)*pi/16));
        
        pxt(1:Nx) = pxt(1:Nx) + (An(n)*cos(wn(n)*t) + Bn(n)*sin(wn(n)*t))*sin(kn(n)*x);
                                 
    end;
    
    figure(1)
    plot(x,pxt)
    title('onda presion sonora');
    xlabel('x (m)');
    ylabel('pxt (m)')
    axis([0, L, -0.6*A, 0.6*A])
    grid on;
    box on;
    
    pause(0.01);
    
end;