how to write the following equation in matlab ?

equation is in attached file, and i am trying like:

%%stair phase
clc;
clear all;
r=1000;
c=1000;
p=32;
N=8;
for i= 1:r
    for j=1:c
        SP(i,j)=(-pi+(i/p)*2*pi/m).*(i/(m*p)=even + (-pi+((i/p)+1)*2*pi/m).*(i/(m*p)=odd;
    end
end
figure(1)
plot(SP);
please help,, where is wrong?

Answer 1

[KSSV]

r=1000;
c=1000;
p=32;
m=8;
SP = zeros(r,c) ;
for i= 1:r
    for j=1:c
        if mod(i/(m*p),2)  %odd 
            SP(i,j) = (-pi+((i/p)+1)*2*pi/m).*(i/(m*p)) ;  %%=odd;

          else   % even 
              SP(i,j)=(-pi+(i/p)*2*pi/m).*(i/(m*p)) ;
          end

      end
  end
  figure(1)
  surf(SP) ;
  shading interp

[ajeet verma]

actually this one is an equation of stair phase and i am not getting the plot as required in attached file after running this code, so please see once it, required graph shown by red color

[KSSV]

What is the the label in y-axis of the figure?

[ajeet verma]

image size is 1024*768