How to generate a random set of x,y coordinates

I am working on a particle tracking project and I need to generate a random set of (x,z) pairs that indacte the particle release location. The coordinates need to be restricted to a box with a xmin,xmax and zmin,zmax. Here is what I have so far.

xmax = 0.4;
xmin = 0.2;
zmin = 0.2;
zmax = 0.32;
xrand = rand(1,400);
xinit = xmin + xrand*(xmax - xmin));

Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.

zrand = rand(1,400);
zinit = zmin + zrand*(zmax - zmin));
P.xp(:,1) = xinit(p);%these are the variables the coordinates will be stored in
P.zp(:,1) = zinit(p);

Answer 1

[Torsten]

xmax = 0.4;
xmin = 0.2;
zmin = 0.2;
zmax = 0.32;
xrand = rand(1,400);
xinit = xmin + xrand*(xmax - xmin);
zrand = rand(1,400);
zinit = zmin + zrand*(zmax - zmin);
P.xp(:,1) = xinit;%these are the variables the coordinates will be stored in
P.zp(:,1) = zinit;

[Sean]

did you change anything?

[Torsten]

Original:

xinit = xmin + xrand*(xmax - xmin));
zinit = zmin + zrand*(zmax - zmin));
P.xp(:,1) = xinit(p);%these are the variables the coordinates will be stored in
P.zp(:,1) = zinit(p);

Modified:

xinit = xmin + xrand*(xmax - xmin);
zinit = zmin + zrand*(zmax - zmin);
P.xp(:,1) = xinit;%these are the variables the coordinates will be stored in
P.zp(:,1) = zinit;

Found the glasses ?