Input Parameters of the Calculation Modul Interpol


Clicking on the menu item Calculation Interpolation…, the following dialog box appears:

 

 

When opening the dialog box, the program reads the batch file with the default name inter.bip, if it exists. Then the default settings in the dialog box may be changed accordingly.

 

 

Output

The text box requires a name for the output file (default: out.i).

 

Interpolation

Here the user decides whether the interpolation is done

 

to node data

to element data (interpolation to the centres of the elements)

for the groundwater contour map (only available in a 2D model)

to a node track

 

The choice of the interpolation data determines the future appearance of the input window.

When choosing ”groundwater contour map” more input possibilities open whereas when choosing “node track“ the block of the interpolation algorithm is closed.

 

Additional data

In this block information is given about the data to be included in the interpolation.

File with interpolation data:

The name of the file with the additional interpolation data is required. It can be typed manually or chosen from the file list (activate the button on the left of the text box). The corresponding file contains only lines with:
Number, x-coordinate, y-coordinate, measured value
When using the format I6, 3F10.2 (equivalent to characteristic data). blank lines between the data are not allowed.

Consider existing data:

The interpolation can consider data already existing in the model file, e.g. potential heads. In such cases, activating the button causes a selection list of existing and anticipated data to appear, from which the user can choose. Pay attention to the units of the data: they can be different from the units in the model file. This selection is only available if node or element data should be interpolated.

Rejection of interpolation points with (minimum) distance:

Data points that are spaced closer than the defined limit with respect to other data points are eliminated. (The interpolation algorithms Gauss and Kriging and the interpolation of a contour map cannot handle double coordinates!)

Lower and upper limit for interpolation values:

The resulting interpolation values can be limited upwards and / or downwards. For instance, terrain settlements as a result of subsurface mining (attribute BERG) should not be less than 0.

Replace interpolation values on GLEI-nodes with average:

In case of interpolation of potential heads from measurements, surface waters connected to the aquifer can be taken into account. With the help of GLEI, the interpolation algorithm allows to use an average value for equal potential heads at the surface waters. This menu item does not apply to the interpolation of element data or if the attribute GLEI is not assigned.

For the interpolation of a groundwater contour map additional auxiliary nodes can be considered. The procedure is described in detail in chapter 1.1.2.

 

 

Interpolation method

Here, the interpolation method is selected that will be used. The following algorithms are available:

 

Distance Weighting

Area Interpolation

Kriging

Gaussian Interpolation

 

By activating one of the algorithms more input options open up that are described in more detail in the chapters below.

 

The buttons in the header of the input window allow the resetting of the input parameters (), the opening of an existing batch file () or the saving of the actual batch file under another name ().

The buttons at the bottom of the input window start the calculation (OK button), close the dialog box (Cancel) or open the digital manual (help button).

 

Distance Weighting