CONT Control points

Columns	format	contents/explanation
1-4	A4	CONT
5-20	A16	Point name
21-30 35-48 49-59	F14.0 F14.0 F11.0	X : Easting Y : Northing Z : Height
60-66 67-73 74-80	F7.0 F7.0 F7.0	sx sy sz	a priori standard deviations of this control point

A coordinate component X, Y or Z as observation is included in the adjustment if the corresponding standard deviation s_x , s_y or s_z is positive. If none of the three standard deviations is provided in a CONT statement or if they are zero, then those default values which were last defined by a COES statement are regarded as standard deviations for this control point. If no COES statement was read previously then the default values are valid (see COES statement).

If, for example, for a control point only the value s_z is positive, then it is a height control point. The same applies for X and Y and all combinations.

The values contained in a CONT statement are also used as approximate values for the point unknowns, namely when

• a coordinate value is given (field not blank) or
• if the standard deviation of the coordinate component is > 0.

The procedure described above is applied for components X, Y and Z separately.