Hi
normally if you move the control points the shape of the curves or the surface changes. but would it be possible to move control points without changing the curves like the picture below?? so that only the control points move and not the shape of the curve??
No…
-Pascal
They are called control points because they control the location and shape of the curve.
Why would you want that?
Just curious
My guess is that he may have seen the extrapolate tool that Icem or vsr have, this is the only way I know to move control points and reduce or increase the original curve without changing the overall shape of the curve.
Hi thanks for the reply
I dont know if this makes sense.
as you see the image I want to move the CP 1 to the CP2 while keeping the shape of the quarter of the circle so that as you see the Left Viewport it becomes “left” curve to the “right” curve.
I make a lot of rings and often I have to spend extra time to maintain the shape of the circle while moving the control points.
if there is a tool it would save a lot more time. 
You seem to have missed the very first two answers.
The basic idea of CPs is that their position will determine the shape of the curve. Moving a single CP will always alter the curve. There might be tools that allow to locally move certain CPs, but they will need to update a few others on the way to keep a semblance of your original shape.
EndBuldge is a command that might do what you want.
Junkim, do you want to change the curve in two views but keep it unchanged in one view?