Float Calculator

v1:
A simple calculator support float over most software interface
you can adjust the interface size by drag the red dot on bottom right corner.
you can minimize the calculator by click left bottom corner icon.
you can close the program by click the red dot.
v2:
new advance functions available!
(not support Operator precedence yet)
you can access them by click the title bar.
support hide window to notification bar
more touch friendly