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Manual for Fluviz v2.0
This document describes the use and the possibilities of the data
processor
Fluviz.
Fluviz is useful
to generate,
alter and analyse spatial data (e.g. digital elevation models, or
land
coverage information). It is mainly written as a compagnion to
two-dimensional
surface flow models. The main options are:
- File reads data from ASCII-files and
exits the program.
- Edit for editing existing data sets.
- Map for surface interpolation (gridding)
and mapping
of nodes.
- Set displays and performs operations on
structured data
sets (grids).
- Export saves data sets in various file
formats.
The plotting in Fluviz is performed by routines that
are derived
from the interactive grafic library GraficV3.
These routines enable to plot lines, vectors, contours (mono and
color)
and animated plots. Drivers are available for X11 and Postscript.
The Keep file option allows to overlay
previously
stored grafical data and bitmap data (pbm-format). Grafic features
such
as lines and filled polygons can be stored in Data Exchange Format
(DXF).
File
FILE reads ASCII-data from files. The data can be structured (grids)
or
unstructured (points and vertices).
Usually the original data is unstructured, e.g. random
distributed points
and vertices. LOAD reads from a file and overwrites existing data.
If
the
data are stored on different files, ADD reads from these files
without
removing the existing data.
The syntax of the ASCII-file is:
>>unstruct is used for unstructured data input.
xyz i1 i2 i3 is unstructured input given in x,y,z coordinates. The r11 r12 r13 i1, i2 and i3 defines the number of the columns where r21 r22 r23 the x, y and z values are stored, respectively. . . . (Defaults: i1=1, i2=2, i3=3)
lines defines break lines given as polygons, where the x,y,z r11 r12 r13 i1 values are stored in the first, second and third column. r21 r22 r23 i2 A point that is a start point of the polygon is flagged in the fourth column with an integer (e.g. i=1, else i=0).
cs 'name' r1 r2 r11 r12 is a record for the cross-section definition. r12 r22 The name of the cross-section (character*8) is ignored. . . r1[km] is a distance along the river (ignored) and r2[m] is the elevation of the bed level. The offset (i.e. distance from the left border) is stored in the first column and the bed level is stored in the 2nd column.
locate r1 r2 r3 is used to locate sections. r1[m],r2[m] are the x,y coordinates of the origin of the section, and r3[degree] is the angle of the section measured clock wise from the y-axis.
item 'name' can be used to identify the following data record.
move r1 r2 translates nodes and lines to east (r1) and north (r2).
rotate r rotates the coordinate system in clock-wise direction with the angle r [degree] with the origin as centre.
xclip r1 r2 range of clipping area in x-direction (values outside are ignored). yclip r1 r2 range of clipping area in y-direction (values outside are ignored).
>>grid is used for structured input.
nx i is the number of grids in x-direction. ny i is the number of grids in y-direction.
xllcorner r r[m] is the x-coord of the lower-left corner. yllcorner r r[m] is the y-coord of the lower-left corner.
dx r r[m] is the distance between grid lines in x-direction. dy r same as for dx but in y-direction.
item 'name' is followed by a list of nx*ny values. row1 ... row2 ...
>> denotes the end of the input. Any further input is ignored.
Edit
The EDIT option allows to process unstructured data sets. The
main options
are:
- Filter: buffering of points close to vertices;
weeding
of vertices
(recursive Douglas-Peuker algorithm); cleaning of points with
same
co-ordinates;
closing of polygons
- Alter: defining operations (+,-,*,/,<,>) that
are applied to
the all given nodes or nodes within a polygon defined by
vertices. The
READ option allows to read the operator and the polygon
information
from
a file. The syntax for such a file is:
fill =1.0 x1 y1 fills the area of the polygon defined by the x/y co-ordinates x2 y2 with the value 1.0. . . . . fill +1.0 x1 y1 adds the value 1.0 to the area defined by the closed polygon. x2 y2 . . . .
The keyword end is used to separate polygons on the same
file.
Example I: Fill an area with the constant value of 0.04 (e.g.
Manning
value):
fill =0.04 691550 272415 691717 272433 691864 272509 691873 272667 691857 272663 691830 272558
Example II: Add 10 meters to the nodes within the two polygons given
below.
fill + 10.0 691393 272300 691423 272342 691455 272379 691503 272393 691551 272405 end 691550 272415 691717 272433 691864 272509 691873 272667
New allows to add points and vertices to existing data.
First a
z-value can be defined that applies to all new points and
vertices.
Points
and vertices are added with the POINT and LINE options. In
addition new
edges between existing points can be created with the EDGE
option.
Map
The Map option allows to transform data from unstructured into
structured
data format. After reading the unstructured data (using the FILE
commands) an interpolation algorithm is applied to create a
structured
rectangular grid. The interpolation is used as the points of the new
grid
do not coincide with the given data points.
The following interpolation methods can be used:
The Map suboption allows to perform operations on a TIN surface.
-
Alter: For operations on z-values of the TIN nodes ( see
operations for
unstructured data in the EDIT option).
-
Map: Allows to map a .node file or unstructured data sets on a
TIN.
-
Inquire: To query z-values for given points and vertices. The
input is
either points and sections from the cursor or co-ordinates from
a file
(with x- and y-values in the 1st and 2nd row, respectively). The
Channel
option allows to query the geometry of cross-sections along a
channel
axis
that is read from a file.
Set
SET enables to display GIS-like plots of grid data and to
perform
some basic operations and function to structured data sets.
-
MOVE for a shift of the x-y coordinates
-
ABSOLUTE values of a set
-
SLOPE and ASPECT operations for a terrain model
-
MAXIMUM value of two sets
-
MINIMUM value of two sets
-
DIFFERENCE between two sets
The results are stored either in the same data set or in a different
set
as specified.
Export
The results from PRE can be exported in different file formats:
-
JUST stores results on a file that can be read by Hydro2de.
-
XYZ stores results on file with the x- and y-coordinates in the
1st and
2nd column, and the parameter value in the 3rd column.
-
GIS prints value to a file with the point number in the 1st
column, the
x- and y-coordinates in the 2nd and 3rd column, and the
parameter value
in the 4th column.
-
ADASSPOINT stores point values of results in ADASS format.
-
ADASSPOLY stores polygon values of grid cells in ADASS format.
-
NODE/POLY is used to store unstructered data in
.node and
.poly
format to be used in TRIANGLE.
-
UNSTRUCTstores points and vertices for input into Fluviz..
-
OMIT asks for a real number. Data points with smaller values are
omitted
when printed to the files specified above.
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