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Minor bugs and request - Printable Version

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Minor bugs and request - Han - 09-23-2014 08:53 PM

Request: Have the second parameter of STARVIEW() accept more than just a 0 or non-zero value. Perhaps 0,1, and -1 where -1 indicates that this particular view "pauses" programs until the user exits that view. For example, I would like save the user's functions, insert my own set of functions, plot via STARTVIEW(1,1) and have the program pause there so that they can explore the functions I want them to see. Then the user presses [Esc] or any key that would normally change views and the rest of my code that comes after the STARTVIEW(1,1) command gets executed.

Right now, STARTVIEW() will change the view, but it doesn't actually produce an updated screen (in some instances) until after the rest of the program is completed. For example, the code below doesn't actually produce the plot I want until I press the OK menu button -- which is normally what is done when the program is finished. Moreover, if I uncomment the call to STARTAPP("Function") then nothing gets drawn Undecided

Code:
export funcs:={"","","","","","","","","",""};

export contours()
begin

  local i,s;

  startapp("Advanced Graphing");

  for i from 0 to 9 do
    s:=left(STRING(i),1);
    iferr funcs(i+1):=expr("STRING(V"+s+")"); then end;
    expr("V" + s + ":=" + STRING("X^2+Y^2=" + s) + ";");
    CHECK(i);
  end;

  startview(1,1);

  for i from 0 to 9 do
    s:=left(STRING(i),1);
    expr("V" + s + ":=" + STRING(funcs(i+1)) + ";");
  end;

//  startapp("Function");

  return(0);
end;

The only other way to draw a function via a program is the force the geometry app to run, and use the plotcontour() command appropriately. This, incidentally, lead me to find a small bug:

Bug: In the CAS view, type: plotfunc(x^2) and you will see a miniature picture of the parabola. Now press the [Help] key and scroll the text you see. The tiny plot blinks in and out.