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iMOD User Manual version 5.2 (html)


8.4GEN-FUNCTIONS


8.4.1GENSNAPTOGRID-Function

The GENSNAPTOGRID function can be used to rasterize a GEN file for a given raster. This gives more grip on the way these GEN files will be applied in a model for particular cell sizes. This GEN file can be transformed into a 3D GEN file as well.

FUNCTION=

GENSNAPTOGRID

GENFILE_IN=

Enter the name of a GEN-file, e.g. GENFILE_IN=D:\DATA\AREA.GEN. These vertices in the GENFILE will be rasterized on the specified network via IDFFILE or an entered window and cell size.

GENFILE_OUT=

Enter the name of a GEN-file to be created, e.g. GENFILE_OUT=D:\DATA\AREA_RASTER.GEN.

IDFFILE=
(optional)

Enter an IDF file for which the dimensions will be used to rasterize the specified GENFILE, e.g. IDFFILE=D:\BND\BND.IDF.

WINDOW=
(optional)

Enter the coordinates of the window that need to be computed, solely. Enter coordinates of the lower-left corner first and then the coordinates of the upper-right corner, e.g. WINDOW=100000.0, 400000.0, 200000.0, 425000.0. When WINDOW= is absent, the dimensions of the specified IDFFILE will be used.

CELL_SIZE=
(optional)

Enter the cell size of the grid that need to be used to rasterize the GEN file, e.g. CELL_SIZE=100.0.

I3D=
(optional)

Specify I3D=1 whenever the GEN file need to be transformed into a 3D GEN file. By default I3D=0 and a regular, 2D GEN is created.

IDF_TOP=

Give an IDF file that represents the uppermost values of the GEN file, e.g. IDF_TOP=D:\FAULTS\BR-T-CK.IDF. Specify this keyword whenever I3D=1.

IDF_BOT=

Give an IDF file that represents the lowermost values of the GEN file, e.g. IDF_TOP=D:\FAULTS\BR-B-CK.IDF. Specify this keyword whenever I3D=1.

Example 1

FUNCTION=GENSNAPTOGRID
IDFFILE= D:\BND\BND.IDF
GENFILE=D:\DATA\AREA.GEN
GENFILE_OUT=D:\DATA\AREA_RASTER.GEN

The above mentioned example will rasterize the AREA.GEN on the dimensions of the specified BND.IDF, see the results on the next figure.

pictures/h6-h71/rasterlines.png

Example 2

FUNCTION=GENSNAPTOGRID
IDFFILE= D:\BND\BND.IDF
GENFILE=D:\DATA\AREA.GEN
GENFILE_OUT=D:\DATA\AREA_RASTER.GEN
I3D=1
IDF_TOP= D:\GEOLOGY\TOP_KI.IDF
IDF_BOT= D:\GEOLOGY\BOT_KI.IDF

The above mentioned example will rasterize the AREA.GEN on the dimensions of the specified BND.IDF and generates a 3D GEN using the values of the specified TOP- and BOT IDF files, see the results on the next figure.


8.4.2GEN2GEN3D-Function

The GEN2GEN3D function reads a GEN file and creates a 3-D GEN file (see section 9.11) to be displayed in the 3-D tool or used in the runfile of iMODFLOW.

FUNCTION=

GEN2ISG

GENFILE_IN=

Give a GEN file containing x and y coordinates of GEN segments, e.g. GENFILE_IN=D:\FAULTS\FAULT.GEN.

IDF_TOP=

Give an IDF file that represents the uppermost values of the GEN file, e.g. IDF_TOP=D:\FAULTS\BR-T-CK.IDF.

IDF_BOT=

Give an IDF file that represents the lowermost values of the GEN file, e.g. IDF_TOP=D:\FAULTS\BR-B-CK.IDF.

GENFILE_OUT=

Specify the yielding GEN file, e.g. GENFILE_OUT=D:\FAULTS\FAULT_BR.GEN. Only ESRI-ASCII GEN files are supported.

XSAMPLING=
(optional)

Specify the sampling distance to add z-coordinates to the GEN file, e.g. XSAMPLING=100.0 will add a point each 100 meter. If this keyword is absent, XSAMPLING will be equal to the cell size of the IDF file entered at IDF_TOP.

Example 1

FUNCTION=GEN2GEN3D
GENFILE_IN=D:\MODEL\FAULTS\FAULT.GEN
IDF_TOP=D:\GEOLOGY\TOP_BREDA.IDF
IDF_BOT=D:\GEOLOGY\BOT_BREDA.IDF
XSAMPLING=250.0
GENFILE_OUT=D:\MODEL\FAULTS_BREDA.GEN

Above an example is given how to use the GEN2GEN3D. This example will generate a 3-D GEN file based on top- and bottom elevations of the geological formation BREDA; the result GEN is written in D:\MODEL\FAULTS_BREDA.GEN.