# AVS field file ndim = 3 dim1 = 40 dim2 = 20 dim3 = 30 nspace = 3 veclen = 2 data = float field = irregular label = temperature pressure variable 1 file=./sample.dat filetype=ascii skip=1 offset=0 stride=2 variable 2 file=./sample.dat filetype=ascii skip=1 offset=1 stride=2 coord 1 file=./sample.cod filetype=ascii skip=1 offset=0 stride=3 coord 2 file=./sample.cod filetype=ascii skip=1 offset=1 stride=3 coord 3 file=./sample.cod filetype=ascii skip=1 offset=2 stride=3
# AVS field file
This line is a must at the beginning of the structured cell data file.
Further, small letters, capitals and spaces must be defined precisely.
Any line beginning with # after the first line will be assumed to be a comment.
ndim = <number>
defines the dimension of the calculation space. This denotes the number of
dimensions of the data array itself. Set this value as 1 in the case of scatter
data.
Note that this value has nothing to do with the coordinate information.
Example: ndim=2 #this is 2D data
dim1 = <number>
dim2 = <number>
dim3 = <number>
Defines the data size in the direction of each axis. Depending on the value
of ndim, this is specified as given below.
For ndim=1 Set only dim1 For ndim=2 Set dim1 and dim2 For ndim=3 Set dim1, dim2 and dim3
nspace = <number>
Sets the dimension of the physical space in which data exists. Consequently,
this defines the space in which the data exists and the kind of coordinates
it has.
If X and Y coordinates are defined nspace = 2 If X, Y and Z coordinates are defined nspace = 3
veclen = <number>
Defines the number of data components.
Example: For temperature data only veclen = 1 For temperature and pressure data veclen = 2 for temperature, pressure and density veclen = 3
data = <text>
Specifies the data type of the data components. One of the types given below
is set in the <text> portion.
short byte integer float doubleNote: If there are multiple data components, it is not possible to set each of these components to be of a different type. The type of all the data components have to be the same.
field = <text>
Specifies the information about the coordinates. Depending on how the
coordinate values are to specified, one of the three types given below is
selected.
uniform
Refers to a orthogonal uniformly spaced lattice. In this case, there is no
need of coordinate information. The coordinate portion of the structured data
format becomes redundant and the cell spacing is automatically set to 1.
rectilinear
efers to a orthogonal non-uniformly spaced lattice. In this case, the
coordinates are specified in each of the representative axis directions.
irregular
Any kind of structured cell data can be specified. Coordinate values are
specified for each point. In the cases of the orthogonal uniformly spaced
lattice as well as the orthogonal non-uniformly spaced lattice, if the
coordinate values are specified for each point, then this can be considered
to be of irregular type.
label = <text> <text> .... (option)
A label is attached to every component. In the case of multiple components,
the text strings are separated using spaces. This keyword is an option and is
not a must.
Example: For temperature data only label = temperature For temperature and pressure data label = temperature pressure
max_ext = x-value [y-value] [z-value].....(option)
min_ext = x-value [y-value] [z-value].....(option)
Specify minimum or maximun values of each coordinates. If you define these keywords in the file header, display advanced 3D axis
in the object window. You can see these value is enterd in each modules.
max_val = value [value] [value].....(option)
min_val = value [value] [value].....(option)
Specify minimum or maximun values of each data components.
However these value reflect modules, you need to check in the Enabled check box of All data Dialog Box.
variable n file=<text> filetype=<text> skip=<number> offset=<number> stride=<number> close=<0/1>
variable
A line that starts with this keyword indicates that this information about data .n
This is a number that distinguishes between the different data components. This is an integer that begins from 1.When the number of data components are 3, the example is as given below:variable 1 file=C:/tmp/sample filetype=ascii
variable 2 file=C:/tmp/sample filetype=ascii
variable 3 file=C:/tmp/sample filetype=ascii
file
Specifies the name of the file to read.
The filename can be specified in terms of absolute or relative paths. Further, the directory separator / (slash) can also be replaced by the \(backslash).filetype
The type of the file to be read in is specified as ASCII or binary.For ASCII: filetype=ascii
For Binary: filetype=binary
skip
Specifies the amount to skipped in the beginning of the file. The meaning of this differs based on whether the file is ASCII or binary.For ASCII : Defines the number of lines to be skipped in the beginning.
For Binary: Defines the number of bytes to be skipped in the beginning.If this keyword is not specified, then skip is automatically set to 0.
offset
This can be used only when the file to be read in is ASCII. This keyword is ignored in the case of a binary file. This value specifies the column number from where data is to be read in the row from which the data is read. For example, to read data from the fourth column, offset is specified as 3.
If this keyword is not specified, it is automatically set to 0.stride
Specifies how much to skip between the data. The meaning of this is different based on whether the file is ASCII or binary.
For ASCII:
specifies the number of variables to be skipped between data. If there is more than one space between data, this is seen as a separator.For Binary:
stride means stride forward "stride" * the size of the data type (byte,float,double,integer). When there are 3 data components of 1 byte each, then stride is set as 3.When this keyword is not set, it is automatically assumed that stride = 1.
close
After reading one step, it defines whether or not the current file should be closed before reading in the next step.If the value is 1, the next step would be read in after closing the file.
If the value is 2, the next step would be read in without closing the file.
In case of close=1;
Since the file will be closed after reading the step, skip, stride descriptions in the next step should be defined from the start.
In case of close=0;
After reading the step, the file will not be closed and the file pointer will be kept. Therefore, if the next step is stored within the same data file, you can designate it from that point relatively.
NOTE 1
In case of reading time, variable, coord from the same data file within the same step, file pointers will be controlled separately, therefore close keyword will take effect individually and will not affect the others.
For example. if time and variable 1 are designating the same data file in all the steps and it's close=0 for all of them, variable 1 always starts reading at the end of variable 1 of three steps back.
NOTE 2
if it's filetype=ascii, close=0 will make the file pointer go to the end of the last line and save, rather than going to the last item of step data. This is to simplify the description of the next step.
ndim nspace veclen dim1 dim2 dim3 byte short int float double
Example: offset=28+(dim1*dim2*dim3*4)
coord n file=<text> filetype=<text> skip=<number> offset=<number> stride=<number>
coord
A line starting with this keyword is taken as representing information related to coordinates.n
Is a number used to distinguish different axis directions and is an integer starting with 1. The example given below indicates a case where three coordinate values X, Y and Z are to be defined.Coord 1 represents the X coordinate, coord 2 the Y coordinate and coord 3 the Z coordinate respectively.coord 1 file=C:/tmp/sample filetype=ascii
coord 2 file=C:/tmp/sample filetype=ascii
coord 3 file=C:/tmp/sample filetype=ascii
file
This has the same meaning as that in the data portion.filetype
This has the same meaning as that in the data portion.skip
This has the same meaning as that in the data portion.offset
This has the same meaning as that in the data portion.stride
This has the same meaning as that in the data portion.
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