how do i remove this error? Function definitions are not permitted in this context.

xyRange=[1,5];      %// Starting xy range of particles
numP=3;             %// Number of particles generated each day
vx=0.6; vy=0.4;     %// x and y velocity

X=[]; Y=[];         %// Vectors start out empty

for day=1:10
   %// Generate 3 particles and add to end of vectors X and Y
   X=[X;randi(xyRange,numP,1)]; 
   Y=[Y;randi(xyRange,numP,1)]; 

     %// Move all the particles
     X=X+vx;
     Y=Y+vy;
     end
  plot(X,Y,'kd');
  grid on ;
  axis([1,50,1,50]); 
  function [box] = coord(X,Y)
  for j = floor(X/5)+1;
      k = floor(Y/5);
      box = k*10+j;
  end
  end

Answer 1

[Thorsten]

You can write it w/o a function, and you don't need the inner for j= ... loop:

for day=1:10
   %// Generate 3 particles and add to end of vectors X and Y
   X=[X;randi(xyRange,numP,1)]; 
   Y=[Y;randi(xyRange,numP,1)]; 

       %// Move all the particles
       X=X+vx;
       Y=Y+vy;
       end
    plot(X,Y,'kd');
    grid on ;
    axis([1,50,1,50]); 

    j = floor(X/5)+1;
    k = floor(Y/5);
    box = k*10+j;

end

[sneha kriplani]

hey thanks for ur answer, it helped me sorting out that problem but i was just wondering if u can help me ahead of it also. if u will run this code then it will plot number of particles now i want to count number of particles in each grid box will give u which particle is in which grid but how to add number of particles in each gridbox ??? Thanks in advance

[Adam]

You should give completely new questions their own thread really rather than tagging them onto a comment of an answer.

Answer 2

[James Tursa]

You have your sub function "coord" defined inside your for loop. Move it outside your for loop.

[Adam]

also if that is a script you need to turn the whole thing into a function in order to define subfunctions.

[sneha kriplani]

but i want to take X,Y as input if i put it in the starting will it take X,Y as input ??