Creates a new javafx.beans.binding.BooleanBinding that holds true if the value of a javafx.beans.value.ObservableNumberValue is equal to a constant value.

When comparing floating-point numbers it is recommended to use the equal() method that allows a small tolerance.

Parameters:

op1		the constant value
op2		the ObservableNumberValue

Returns:  the new BooleanBinding

Exceptions:

NullPointerException

if the ObservableNumberValue is null