Understanding the if command

o = B(1:50,2);

a1 = diff(o);

[c1,d1] = find(a1>2^15);

[e1,f1] = find(a1<-2^15);

if c1 > 0;

o(c1+1:e1) = o(c1+1:e1)-2^16;

elseif c1 < 0;

o(c1+1:e1) = o(c1+1:e1)+2^16; % works good

else ; % Basically I need the command to say when e1 = isempty to use the statement below!

o(c(1)+1:end) = o(c(1)+1:end)-2^16;

end

plot(o)

Answer 1

[KALYAN ACHARJYA]

elseif isempty(c1)                                                 
  o(c(1)+1:end)=o(c(1)+1:end)-2^16;
else
      %do nothing
end