ezplot is plotting a blank plot

no errors nut plot is blank

syms y(x)

a=2;

b=6;

c=1;

d= 8;

e = 6;

ode = diff(y,x) == (-d*x)/(e*y);

ysol = vpa(dsolve(ode))

ezplot(ysol(1))

hold on

ezplot(ysol(2))

Answer 1

[Mark Sherstan]

You need to solve for your constant C2 otherwise your function is no longer in terms of just x which is a requirment of ezplot.

[Brenda Galabe]

THIS EQUATION DID PLOT AND IT HAD CONSTANTS TOO, whats the difference between the tw0

syms y(x)

a=2;

b=6;

c=1;

ode = diff(y,x) == (a*x*y)/(b*x^2-c*y^2);

ysol = vpa(dsolve(ode))

ezplot(ysol(1))

hold on

ezplot(ysol(2))

ezplot(ysol(3)

[Cris LaPierre]

You did not try to plot the solution that contains constant C5 (ysol(4)). Your plots are for

• 0
• 2x
• -2x

Answer 2

[Cris LaPierre]

You equation has two variables. You need to provide a value for for ezplot to be able to plot the functions.

Also, best to heed the warnings in the documentation - use fplot instead of ezplot.

If I use fplot and substitute in a value for C2, your code works.

...
ysol = subs(ysol,'C2',25)
fplot(ysol(1))
hold on
fplot(ysol(2))

Answer 3

[Brenda Galabe]

this error happens instead

Index exceeds matrix dimensions.

Error in fplot (line 56)

lims = args{2};

[Cris LaPierre]

I didn't realize you were using an older version of MATLAB. The behavior will be different. Use ezplot for now.