The amounts by which Eq 29.3 and Eq 29.4 fail to be satisfied are called the errors in closure in position or simply the closures of a traverse (Figure 29.2). The closing correction in terms of departure and latitude dD and dL are thus can be found as
dD= (Xn - X1) + S departures --------------- Eq (29.7)
dL= (Yn - Y1) + S latitudes --------------- Eq (29.8)
and the direction of the error q is given by
--------------- Eq (29.9)
The sign of dD and dL finally defines the value of azimuth of error of closure.