The document discusses the release of version 4.3 of a software by Peter Vermeulen, focusing on the use of double precision coordinates in various file types such as idf and isg for improved accuracy. It highlights the conversion between single and double precision, the new binary format for gen-files, and additional features like sorting and interactive tools in imod. Notably, it addresses the limitations of using singular precision for accuracy in coordinate representation.

1. Release v4.3
Peter Vermeulen

2. Recent Developments
LLUR
Landesamt für Landwirtschaft, Umwelt und ländliche Räume
Geologischer Dienst Schleswig-Holstein
• Double precision coordinates
AGS
Alberta Geological Survey
• Extended queries for boreholes
• Artificial Boreholes
• GEN files
16 november 2018

3. Double-Precision
Example in single precision(7 significant) numbers.
120000.0,440000.0
Such a coordinate means that a maximal accuracy of 0.1 can be
obtained. Smaller values of <0.1 meter cannot be projected
accurately.
16 november 2018

4. Double-Precision
Example (ETRS89/UTM) in single precision (7 significant) numbers.
590000.0,5659000
Such a coordinate means that a maximal accuracy of 1.0 can be
obtained. Smaller values of <1.0 meter cannot be projected
accurately.
Usage of double precision enlarges
the number of signifcant numbers to 15.
16 november 2018

5. Double-Precision
iMOD uses a “shadow” coordinate
system
iMODMap
0,01000000,5000000
dx=100,dy=1001000100,5000100
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0,0
dx,dy

6. Double-Precision
16 november 2018
Choice between single- and double precision
– iMOD converts IDF files between single-
and double precision. Besides the
coordinates, the data will be double precision
too (doubles the size of an IDF-file)
IDF Files
Notes:
• If ASCII-files are imported iMOD “sees” whether
the coordinates need to be in double-precision
• If IDF Calc is used, a single- or double-precision is
inherited from the first mentioned IDF-file

7. Double-Precision
16 november 2018
ISG Files Choice between single- and double precision –
iMOD converts ISG files between single- and
double precision. Besides the coordinates, the
data (coordinates, elevations, cross-sections) will
be double precision, also additional attribute time
added to data for future usage

8. Double-Precision
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iMODFLOW:
Choice between single- and double
precision
Running the model (runfile)

9. GEN-files
Current GEN-file
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1
245143,516806
245114,516811
245095,516796
245073,516776
245027,516753
245004,516739
244994,516730
244938,516700
244927,516697
244917,516698
244903,516692
244895,516687
244887,516673
244883,516665
244834,516632
244815,516595
END
END
id,province,capital
1,Drenthe,Assen
2,Flevoland,Lelystad
3,Schiermonnikoog,Schiermonnikoog
4,Ameland,Nes
5,'Het Rif',-
6,Terschelling,West-Terschelling
7,Friesland,Leeuwarden
8,Vlieland,Oost-Vlieland
9,Richel,-
11,Gelderland,Arnhem
12,Rottemerplaat,-
13,Rottemeroog,-
14,Zuiderstrand,-
15,Simonszand,-
Drawback
Very slow drawing
huge GEN-files

10. GEN-Files
ASCII and BINARY GEN-files both supported, however, for several
features in iMOD it is obliged to use the binary format. iMOD offers
the possibility to convert ASCII GEN-files into BINARY GEN-files.
16 november 2018
New BINARY format (*.GEN)
includes coordinates (double
precision) and attributes in a
single file.

11. GEN-files
New BINARY format (*.GEN) displays much-quicker and performances increases if zoomed in
16 november 2018
140MB

12. Resizable and movable scalebar (interactively)
Clipboard takes the selected area
bounded by the axes automatically
Movable axes
(interactively)
Extra’s

13. - Capable of sorting IDF files in the iMOD
Manager based upon keywords, in this
manner it is easy to sort a list as
TOP_L1.IDF, BOT_L1.IDF, TOP_L2.IDF,
BOT_2.IDF etc.
- Select files in the iMOD Manager via a
search string, this is handy to select
multiply files to be given a similar legend
Extra’s

14. Extra’s
Particle Tracking supports the
usage of IPF files (xyz) for
starting points
16 november 2018

15. Extra’s
Interactively Position 2D Layout of line for cross-section
16 november 2018

16. Extra’s
Restored Pumping Tool
16 november 2018