linear mode (Entry: algebraic)

[compsystems]

Hi. Good morning

The following code can be entered directly on the entry line, but only work in CAS and linear mode (Entry: algebraic/1D). Why? the definition failure in textbook mode (aka pretty print or 2D input)

Please copy and paste the following codes into the input line (simulator)

PHP Code:

function fract(X_,Y_,Nmax) // Mandelbrot fractal, not using symmetry.
  local x,y,z,c,j,w,h,res1,res2;
  freeze;
  w:=2.7/X_;
  h:=-1.87/Y_;
  res1:=[]; 
  Y_:=Y_-1;
  for y from 0 to Y_ do
    c:=-2.1+i*(h*y+0.935);
    for x from 0 to X_-1 do
      z:=0;
      for j from 0 to Nmax-1 do
        if abs(z:=z^2+c)>2 then break; end;
      end;
      res1.append(pixon_p(x,y,126*j+2079));
      c:=c+w;
    end;
   end;
  //return res1; // hpprime: comment on this line, 10 thousand elements maximum
   return "Done"
end; 


//deltalist(time(fract(320,240,10)));
fract(320,240,10)

from program editor with please add the header #cas ... #end

PHP Code:

function fract1(X_,Y_,Nmax) // Mandelbrot fractal, using symmetry.
  local x,y,z,c,j,w,h,res1,res2;
  freeze;
  w:=2.7/X_;
  h:=-1.87/Y_;
  res1:=makelist(-ceiling(X_*Y_/2)-1);   
  res2:=res1;
  Y_:=Y_-1;
  for y from 0 to Y_/2 do
    c:=-2.1+i*(h*y+0.935);
    for x from 0 to X_-1 do
      z:=0;
      for j from 0 to Nmax-1 do
        if abs(z:=z^2+c)>2 then break; end;
      end;
      res1.append(pixon_p(x,y,126*j+2079)); 
      res2.append(pixon_p(x,Y_-y,126*j+2079)); 
      c:=c+w;
    end;
  end;
  //return res1,res2; // hpprime: comment on this line, 10 thousand elements maximum 
  return "Done" 
end; 


//deltalist(time(fract1(320,240,10)));
fract1(320,240,10)