Apply Levels

Use the Database Tools > Channel Tools > Apply Levels menu option (LEVEL GX) to adjust the values of an input channel so that they match the values of a given control channel wherever the control channel values are defined (not dummy).

Apply Levels dialog options

Channel to level	Input channel Script Parameter: LEVEL.IN
Level reference channel	Control channel Script Parameter: LEVEL.CONTROL
Output leveled channel	Output leveled Channel Script Parameter: LEVEL.OUT
Leveling mode	"Match", "Minus" or "Plus": "Match" mode moves the Input channel to match the actual value of the control channel. "Minus" subtracts a linear interpolation of the control channel from the input channel. "Plus" adds a linear interpolation of the control channel to the input channel. The default setting is "Match". Script Parameter: LEVEL.MODE

Application Notes

The LEVEL GX adjusts a data channel based on the values defined in a control channel. The control normally contains values only at certain 'control' points, such as the intersection with a tie line. LEVEL will adjust the input data based on these control points using by either matching the values or applying a simple plus or minus shift of the data.

For a match movement the input channel values are moved so that the absolute value of the control points is matched.

For Plus or Minus moves, the control channel is added or subtracted from the input channel.

The input data is adjusted assuming a linear distribution of error between control points defined in the control channel. If you would like a smoother adjustment, the control channel can be replaced by a smooth correction channel either by splining the data (see INTERP), which fits the control points exactly, or by polynomial regression (see TREND).To achieve a smooth interpolation for match levelling, first subtract the control channel from the level channel, smooth the result, then apply LEVEL using the Minus option.

The INTERSCT, XLEVEL and LEVEL GX methods allow you to perform tie-line levelling of data.