function tempConvGUI
% a simple temperature conversion window
global tempConvState; %! set up the state
[f,c,m] = tempConvFig;
tempConvState.f = f;
tempConvState.c = c;
tempConvState.m = m;
set(f,'Callback', 'fahrenheitEntry'); %! set callbacks
set(c,'Callback', 'celsiusEntry');