hysteresis comparator calculation

note: use the minus sign "- for negative voltage". )
positive supply voltage: positive supply voltage: (V)
negative supply voltage: negative supply voltage (V)
result:
vth (high threshold voltage): threshold voltage (high level threshold voltage)
(V)
r2/r1 (proportional resistor):
vtl (low threshold voltage)::threshold voltage (low level threshold voltage)
(V)
vr (reference voltage):
(V)