How do you save variables to vectors and plot them?

This is my code:

valueOfP = [];
valueOfD = [];
valueOfT = [];
valueOfH = [];


  Irrelevant code that functions on its own
end
    fprintf(' Altitude is %d   Temp = %d  Pressure = %d  Density = %d \n', h, t, p, d)
 
end  
  valueOfP(h) = p;
    valueOfD(h) = d;
    valueOfT(h) = t;
    valueOfH(h) = h;
    plot(valueOfP,valueOfH)
    plot(valueOfT,valueOfH)
    plot(valueOfD,valueOfH)

I keep getting error messages when I try to run the code. How would I go about saving the variables and then plotting pvs h, t vs h, and d vs h?

[madhan ravi]

dipidi dapudi doo , totally vague

[madhan ravi]

post your code or upload your script file

[Macy Walters]

g = 9.807;
r = 287;
a1 = -.0065;
a3 = -.0045;
a2 = .003;
a4 = .004;
e = exp(1);

valueOfP = [];
valueOfD = [];
valueOfT = [];
valueOfH = [];

h1=0;
T1 = 288.16;
P1 = 101325;
D1 = 1.225;

P0 = P1*(1+(a1/T1)*(h-h1))^(g/(a1*r));
D0 = D1*((1+a1/T1)*(h-h1))^(g/(a1*r)+1);

h2=11;
tx1 = 216.66;
px1 = P0*e^((-g/(r*t0)*(h-h2)));
dx1 = D0*e^((-g/(r*t0)*(h-h2)));

h3=25;
t2=216.66;
p2 = p1*(1+(a2/t2)*(h-h3))^(g/(a2*r));
d2 = d1*((1+a2/t2)*(h-h3))^(g/(a2*r)+1);

h4=47;
t3 = 282.66;
p3 = p2*e^((-g/(r*t3)*(h-h4)));
d3 = d2*e^((-g/(r*t3)*(h-h4)));

h5=53;
t4 = 282.66;
p4 = p3*(1+(a3/t4)*(h-h5))^(g/(a3*r));
d4 = d3*((1+a3/t4)*(h-h5))^(g/(a3*r)+1);

h6=79;
t5 = 165.66;
p5 = p4*e^((-g/(r*t5)*(h-h6)));
d5 = d4*e^((-g/(r*t5)*(h-h6)));

h7=90;
t6 = 265.66;
p6 = p5*(1+(a4/t6)*(h-h7))^(g/(a4*r));
d6 = d5*((1+a4/t6)*(h-h7))^(g/(a4*r)+1);

h=0;
for h=0:.5:105
    
    if (0<=h&&h<11||53<=h&&h<79)
        if(0<=h&&h<11)
            h1=0;
            t1 = 288.16;
            p1 = 101325;
            d1 = 1.225;
            t = t1+a1*(h-h1);
            p = P0*(1+(a1/t1)*(h-h1))^(g/(a1*r));
            d = D0*((1+a1/t1)*(h-h1))^(g/(a1/r)+1);
        else
            h1=53;
            t1 = 282.66;
            t = t1+a3*h;
            p = p4*(1+(a3/t1)*(h-h1))^(g/(a3*r));
            d = d4*((1+a3/t1)*(h-h1))^(g/(a3/r)+1);
        end
        
    elseif(11<=h&&h<25||47<=h&&h<53||79<=h&&h<90)
        if(11<=h&&h<25)
            h1=11;
            t = 216.66;
            p = px1*e^((-g/(r*t)*(h-h1)));
            d = dx1*e^((-g/(r*t)*(h-h1)));
        elseif(47<=h&&h<53)
            h1=47;
            t = 282.66;
            p = p3*e^((-g/(r*t)*(h-h1)));
            d = d3*e^((-g/(r*t)*(h-h1)));
        else
            h1=79;
            t = 165.66;
            p = p5*e^((-g/(r*t)*(h-h1)));
            d = d5*e^((-g/(r*t)*(h-h1)));
        end
        disp('The temperature is')
        disp(t)
        disp('The pressure is ')
        disp(p)
        disp('The density is ')
        disp(d)
    else
        if(25<=h&&h<47)
            h1=25;
            t1=216.66;
            t = t1+(a2*(h-h1));
            p = p2*(1+(a2/t1)*(h-h1))^(g/(a2*r));
            d = d2*((1+a2/t1)*(h-h1))^(g/(a2*r)+1);
        elseif(90<=h&&h<105)
            h1=90;
            t1 = 165.66;
            t = t1+a4*(h-h1);
            p = p6*(1+(a4/t1)*(h-h1))^(g/(a4*r));
            d = d6*((1+a4/t1)*(h-h1))^(g/(a4*r)+1);
        end
    end
    fprintf(' Altitude is %d   Temp = %d  Pressure = %d  Density = %d \n', h, t, p, d)
    
end
valueOfP(h) = p;
valueOfD(h) = d;
valueOfT(h) = t;
valueOfH(h) = h;
plot(valueOfP,valueOfH)
plot(valueOfT,valueOfH)
plot(valueOfP,valueOfH) 

Answer 1

[KSSV]

x = zeros([],1) ;
y = zeros([],1) ; 
for i = 1:10 
    x(i) = i ;
    y(i) = rand ;
end
plot(x,y) ;

[Macy Walters]

Error in HWM3 (line 131)

valueOfP(h) = p;

Say That i tried to run the code and got this, how would i fix this error? Thank you

[KSSV]

You should specify the error.....how you expect us to correct it without code and showing us the error.

Answer 2

[Stephen23]

You define h to have values that are NOT positive integer:

for h=0:.5:105

which means that you cannot use h as an index. The simplest solution is to define a vector of h values, and loop over its indices. For your code you will need to do something like this:

hvec = 0:.5:105; % vector of h values
N = numel(hvec);
Pvec = nan(1,N); % preallocate output
Dvec = nan(1,N); % preallocate output
Tvec = nan(1,N); % preallocate output
for k = 1:N      % loop over indices
    h = hvec(k);
    ... your code
    Pvec(k) = p;
    Dvec(k) = d;
    Tvec(k) = t;
end
plot(hvec,Pvec)
figure()
plot(hvec,Dvec)
figure()
plot(hvec,Tvec)