I have a physical equation P=(n R T/V - nb)-(an^2/V^2)
which n,b,a,R are constants and V,T are independent variables
the question said to construct an anonymous function (pressure)>P and then create a script function called (
vanderWall) which return P,V,T and make mesh contour plot of (P,V,T) and plot of (P,V) for 10 values of T.
the function should generate T with limits T1 to T2 with nT steps, also generate V with limits V1 to V2 with nV steps
using these values for practical output
T1=77, T2=800, nT=10, V1=35, V2=200, nV=150, n=1, a=55.37, b=30.4.
I tried this code put no usefull answer
%constants
n=1;
a=55.37;
b=30.4;
R=8.314;
%anonymous function of independent variables V and T
Pressure=@(V,T) ((n*R.*T)./(V-n*b))-((a*n^2)./V.^2);
[P,V,T]=vanderWall(Pressure,77,800,10,35,200,150,1,55.37,30.4);
%function to return Pressure,Volume and Temperature
function[P,V,T]=vanderWall(Pressure,T1,T2,nT,V1,V2,nV,varargin)
%Volume and temperature generatd by function
T=T1:nT:T2;
V=V1:nV:V2;
P=Pressure(V,T);
%mesh contour plot between T,V and P
meshc(T,V,P)
%plot of V and P (isotherms)
plot(V,P)
end
Maybe you can try the following code for function vanderWall, where [T,V]=meshgrid(t,v) is the key step to make your code fly
function[P,V,T]=vanderWall(Pressure,T1,T2,nT,V1,V2,nV,varargin)
%Volume and temperature generatd by function
t = T1:nT:T2;
v = V1:nV:V2;
[T,V]=meshgrid(t,v);
P=Pressure(V,T);
%mesh contour plot between T,V and P
meshc(T,V,P)
%plot of V and P (isotherms)
plot(V,P)
end
Or you can apply the implicit singleton expansion (thanks for advice @CrisLuengo), i.e.,
function[P,V,T]=vanderWall(Pressure,T1,T2,nT,V1,V2,nV,varargin)
%Volume and temperature generatd by function
T = T1:nT:T2;
V = V1:nV:V2;
P=Pressure(V,T.')';
%mesh contour plot between T,V and P
meshc(T,V,P)
%plot of V and P (isotherms)
plot(V,P)
end