Pass the answers of ode45 over to another function and solve the simultanous equation

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a1=28*7*400; %%ft^2
po=40.6; %%psi
delpio=9; %%psi
qf=1525; %%gpm
qo=qf;
pp=16.4; %%psi
qp=1234; %%gpm
depr1=24.9; %%psi
delpr2=18.2; %%psi
PH=360; %%ft
lp=2.76*.264/(60)^2*14.5; %%gal/m*min^2/psi
k2=1.75*10^-4*60^1.67*14.5/264.172^1.67; %%psi/(gal/min)^1.67
k3=2.27*10^-2; %%(m^3/h)^.6/m^2
g=32.17; %%ft/s^2
rhoh20=62.4; %%lbs/ft^3
pf=rhoh20*g*PH*1.488*.000145; %%psi
delpo=pf-po; %%psi
icQ=qo;
icdelp=delpo;
xo=0;
xspan=[0 50];
jw=JW(lp,qo,delpio,k3,y,xo,z);
[x,y]=ode45(@odes,xspan,xo)
function F=JW(lp,qo,delpio,k3,y,xo,z)
F=fsolve(@findjw,xo);
function F=findjw(z)
F=lp*(y(2)-qo*delpio/y(1)*exp(z/(k3*y(1)^0.40)))-z;
end
end
function dydx=odes(jw,a1,k2)
dydx=zeros(2,1);
dydx(1)=-jw*a1;
dydx(2)= -k2*y(1)^1.67;
end
Undefined function or variable 'y'.
Error in mhlro (line 25)
jw=JW(lp,qo,delpio,k3,y,xo,z);
I would like to pass the solution from the ode 45 of function odes() over to function JW(). Both these equations are dependent of each other. i would like to solve for jw
  2 Comments
Sriram Tadavarty
Sriram Tadavarty on 13 Mar 2020
The error comes due to variable y not defined before the call to function JW. Please define y(1) before the function calls to JW and odes. This should solve.
Rodrigo Blas
Rodrigo Blas on 13 Mar 2020
xo=0;
xspan=[0 50];
y=zeros[2,1];
y=ode45(@odes,xspan,xo)
jw=JW(lp,qo,delpio,k3,y,xo,z);
Error: File: mhlro.m Line: 24 Column: 8
Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for
mismatched delimiters.
okay. Im trying to get y to be the answer from the ode and pass it onto JW() but i get this error

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