This section describes functions from file files.ct.
[] = export_matlab(fn...)
export_matlab("file") saves all variables in Tela
workspace in "file". Any previous contents of "file"
are overwritten. The data are written in MATLAB
binary format. Hidden Tela variables are not saved.
export_matlab("file","var1","var2"...) saves only the
specified variables. Notice that you have to give the
variable names as strings.
The resulting MAT-file can be read using the
MATLAB 'load' command.
Limitations (bugs): It is not possible to export
local variables. If you try, the global ones will
be written, if they have numeric values. Use
export_matlab2 to achieve this, and to have explicit
control of variable naming.
See also:
export_matlab2,
save,
load,
import.
Error codes:
1: Too few arguments
2: Argument not a string
3: Write error on file
[] = export_matlab2(fn...)
export_matlab2("file", var1,"name1", var2,"name2"...)
saves objects var1,var2... in MATLAB binary format in "file".
The objects will be named "name1", "name2"... .
Any previous contents of "file" are overwritten.
workspace in "file". Any previous contents of "file"
is overwritten.
The resulting MAT-file can be read using the
MATLAB 'load' command.
See also:
export_matlab,
save,
load,
import.
Error codes:
1: First arg not a string
2: Even number of arguments
3: Write error on file
4: The 'name' argument is not a string
[] = export_netCDF(fn...)
export_netCDF("file",...) behaves exactly like
save but it exports the variables in netCDF rather
than HDF format. The function is operational only
if NewHDFSupported() returns nonzero.
See also:
save,
HDFNewMode.
Error codes:
1: Too few arguments
2: Argument not a string or char
3: Unexpected HDF error
4: Cannot open new-style HDF SD file
5: Cannot create netCDF file
6: netCDF not supported by this Tela, use HDF4.0b1 or later
[] = export_PNG(fn,r;g,b,a)
export_PNG("file.png",u)
writes integer matrix u into grayscale PNG file.
export_PNG("file.png",u,a) writes grayscale and alpha data.
export_PNG("file.png",r,g,b) writes RGB colour data.
export_PNG("file.png",r,g,b,a) writes RGB and alpha data.
The bit depth will be 8 or 16, depending on whether maxval
is less than 256 or not. Negative values are silently
replaced by zero.
Error codes:
1: First arg not a string
2: Cannot open output file
3: Cannot write PNG header to output file
4: Second input arg not integer matrix
5: Third input arg not integer matrix
6: Third input arg is different size matrix than second arg
7: Fourth input arg not integer matrix
8: Fourth input arg is different size matrix than second arg
9: Fifth input arg not integer matrix
10: Fifth input arg is different size matrix than second arg
[] = export_PNM(fn,r;g,b)
export_PNM("file.pnm",x) writes integer matrix x in
PNM (Portable aNyMap) file "file.pnm". If no element is
larger than 255, a 8-bit "raw" file is written, otherwise an ASCII file.
If all elements are equal to 0 or 1, a black and white 1-bit PBM
(Portable BitMap) file will be written.
export_PNM("file.pnm",r,g,b) creates a 24-bit color-PPM file.
Matrix entries are truncated in the range 0..255 in this case.
The integer matrices r,g and b represent the red, green
and blue values. They must have equal dimensions.
If the system supports pipes (has the popen function),
you can use export_PNM("!...",..) to write to a pipe instead
of a file (for example, export_PNM("!cjpeg >x.jpeg",r,g,b)).
See also:
import_PNM.
Error codes:
1: First arg not a string
2: Argument is not integer matrix
3: export_PNM must be called with 2 or 4 input args
4: Dimensions of R,G,B matrices must be equal
5: Could not open file for output
[] = export_RIS8(fn,x)
export_RIS8("file.hdf",x) writes (appends) integer matrix x
to HDF file "file.hdf" as a raster-8 image (Raster Image Set, RIS).
When the file is opened with default settings using the usual
HDF viewers such as Spyglass products, the first dimension grows
vertically downward and the second dimension grows from left to
right.
The RIS8 HDF files can be read back using import.
See also:
export_matlab,
save,
import.
Error codes:
1: First argument not a string
2: Second argument not an integer matrix
[] = export_sound_CDR(fn,L,R)
export_sound_CDR("file.cdr",left,right)
takes integer-valued vectors left and right and writes them in
raw audio-CD format in "file.cdr". The file will consist of 16-bit
signed sample pairs (left,right).
If the filename starts with "!", it is interpreted as an output pipe.
Error codes:
1: First arg not a (nonempty) string
2: Second arg not an int vector
3: Third arg not an int vector
4: Second and third args of unequal lengths
5: Cannot open output file
6: This Tela implementation has sizeof(short)!=2, cannot do export_sound_CDR, sorry
7: Not enough memory for work arrays
8: File write incomplete, maybe filesystem full
[;y] = HDFNewMode(;x)
HDFNewMode(1) causes subsequent save calls to write the data
in "new" style HDF files, using the SD rather than SDS interface,
which is nowadays the default.
The old style SDS interface is used by subsequent saves after
calling HDFNewMode(0).
This function works only if you have compiled Tela with HDF4.0b1
or newer and Tela version 1.23 or later. Whether this is the case
can be tested by calling NewHDFSupported().
See also:
NewHDFSupported,
save.
Error codes:
1: Argument not integer
2: New HDF mode not supported by this Tela
[] = import(filename; appendix)
import("file") tries to load the contents of "file" in
Tela workspace. All files accepted by load are also accepted
by import. In addition, import accepts more general HDF files
(SDS and 8-bit raster image files) as well as MATLAB binary
files (MAT-files).
import("file","app") appends the string "app" to the name
of every variable imported.
Restrictions:
1) If file is HDF-file, import first tries to read all SDSs. Only
if none was found, it tries to read all RIS8 datasets. The
variable names are taken from the HDF labels, if the labels have
been set. If there are no labels, the variables are named
"Dataset1", "Dataset2", ... and "Image1", "Image2",... for SDS and
RIS8 imports, respectively.
2) Only read Matlab version 4 format (Actually Level 1.0, as
written by matlab version <= 4 and on request on newer versions).
For filename conventions, see load.
See also:
load,
save,
import1,
export_matlab,
export_RIS8,
import_PNM.
(The difference between import and import1 is that import1 reads
only one object and returns it, whereas import reads several
objects and assigns them directly to workspace variables.)
Error codes:
1: First arg not string
2: First arg is not an HDF file
3: File not found
4: Cannot import file
5: Unused error message
6: Cannot import file, internal Matlab file error
7: Cannot import this Matlab file, unknown data format
8: Cannot import this Matlab file, it is a sparse matrix. Make it full before saving.
10: Bad Matlab binary file, premature end of file
11: Second argument not a string
12: Cannot import this Matlab file, it contains VAX or CRAY floating point
[r;g,b,a] = import_PNG(fn)
[r,g,b] = import_PNG(fn)
reads in a PNG file and places the red, green and blue components
in matrices r,g and b, respectively. If the file is grayscale,
r, g and b will have the same value.
u = import_PNG(fn) reads a grayscale image into u.
If file has colour information, the average of R, G and B
components is placed in matrix u.
[r,g,b,a] = import_PNG(fn) reads also the alpha channel.
If no alpha channel is stored in the file, a will be set to 255.
Limitations/bugs: Reading interlaced PNG files is not yet supported.
Error codes:
1: Cannot open input file
2: Input file is not PNG file
3: Bad format inside input PNG file
-1: Input arg not a string
[r;g,b] = import_PNM(fn)
x = import_PNM("file.pnm") reads PNM (Portable aNyMap) format image file.
x will become integer matrix.
[r,g,b] = import_PNM("file.pnm") reads a color image
and assigns the red, green and blue components to
matrices r,g,b.
All six PNM formats (P1-P6) are recognized. If a color
image (P3 or P6) is loaded using only one output argument,
the average of color components is computed and assigned
to x. If a greyscale image is loaded using three output
args, only the first (r) output arg will be filled,
g and b are assigned the VOID value. You might use
a code like
[r,g,b] = import_PNM("file.pnm");
if (isvoid(g)) {g=r; b=r};
to continue processing in 24-bit mode.
If the system supports pipes (has the popen function),
you can do import_PNM("!...") to read from a pipe.
For example, import_PNM("djpeg x.jpg").
See also:
import,
export_PNM.
Error codes:
-1: First arg not a string
2: Could not open input file
3: Input file is not PNM file
4: Width or height not positive - improper PNM file
5: Invalid color range
-6: Two output args, give 1 or 3
7: Error when reading ASCII data
8: Pixel not 0 or 1 in 1-bit image
10: Could not read all binary data
[x] = import1(filename; label)
import1("file") reads one object from "file". The imported
object is returned. "File" can be one of the following:
1) HDF file, in which case the first Scientific Data Set (SDS)
is imported. The form import1("file.hdf","label") reads SDS
with label "label", which is not necessarily the first one.
2) D-style ASCII file of the following format:
(line 1) D=Nt dim1 dim2 ... dimN
(any number M of blank lines or lines starting with '#')
(line M+2) data1 data2 ....
where N is the rank of the dataset and t is an optionial
type specification letter: t may be either 'r', 'i', or 'c'
for real, integer and complex data, respectively. If t is
missing, real data are asssumed.
3) Plain ASCII file of nrows x ncols real numbers. If nrows or
ncols is 1, it will be returned as a vector, otherwise as a
matrix. Missing entries are treated as zeros. This format
is similar to Matlab's load for ASCII, except that '#'
comments are accepted (for vector files, '#' comments are
accepted only in the beginning).
See also:
import,
load,
save.
See import for a difference between import and import1.
For filename conventions, see load.
Error codes:
-1: Input arg not a char or string
2: File not found
3: Unknown format in ASCII file
4: Unknown format in ASCII file
5: Too high rank ASCII data
6: Syntax error in ASCII file dimension specification
7: Syntax error when reading D-style ASCII data
-8: Internal error
-9: Cannot import file
-10: Second arg not a string
11: Specified label not found
12: Premature end of file in D-style ASCII
13: Syntax error when reading plain ASCII data
14: DFSDgetdims error
15: DFSDgetdata error
[] = load(filename)
load("file") loads the contents of "file" in Tela workspace.
"file" must have been previously created using the 'save'
command; it must be in a certain HDF format.
Filename conventions:
If the filename starts with "/", "./" or "..",
it is considered absolute. Otherwise it is searched
along TELAPATH. This applies to other file
operations as well.
The counterpart of load is save.
To read more general HDF files and ASCII files, see import1.
To load more general HDF files and MATLAB binary files,
see import.
See also:
save,
import,
import1,
export_matlab.
Error codes:
1: Argument not string or char
2: Argument is not an HDF file
3: File not found
4: Argument is not an HDF or netCDF file
5: Cannot load this HDF file
6: HDF file load incomplete
[y] = NewHDFSupported()
NewHDFSupported() returns 1 if this Tela was compiled with
HDF4.0b1 or later. If this is the case, then the following
become possible:
- HDFNewMode(1) can be used to save HDF data in "new" format
(SD rathern than SDS interface). This is now the default!
- Unidata netCDF files can be loaded/imported in the same
way as HDF SDS/SD files
The main benefit of using the new format is that no precision
loss occurs because 64-bit numbers are used for real data
(the old HDF interface only supports 32-bit data).
The main drawback of using the new format is that old Tela
versions and Tela versions which are still compiled with
HDF3.1r5 can not read the files. The old style files can be
read by all Tela versions.
See also:
HDFNewMode,
save.
[] = save(fn...)
save("file") saves all variables in Tela workspace
in "file". Any previous contents of "file" is
overwritten. The data are written as Scientific
Data Sets in HDF format. Hidden variables are not saved.
save("file","var1","var2"...) saves only the
specified variables. Notice that you have to give
the variable names as strings.
Limitations (bugs): It is not possible to save
local variables, since they are not bound to
symbols. If you try, the global one, if any,
will be saved.
See also:
HDFNewMode,
load,
export_matlab,
export_netCDF.
Error codes:
1: Too few arguments
2: Argument not a string or char
3: Unexpected HDF error
4: Cannot open new-style HDF SD file