This section describes the functions about the data initialization, import and export.

Initialization

clear

Description
Clears all or specified stored workspace variables.
Used in FDTD and FDE.

Syntax

Example

b = 1;
c = 2;
 
clear( 'b' );

clearall

Description
Clears all workspace variables.
Used in FDTD and FDE.

Syntax

See also
clear

clc

Description
Clears script console.
Used in FDTD and FDE.

Syntax

See also
clear

delete

Description
Deletes the selected objects.
Used in FDTD and FDE.

Syntax

Example

Delete the index monitor named "new_index_monitor" of FDTD Solver.

delete('FDTD::new_index_monitor');

See also
clear

deleteall

Description
Deletes all the objects.
Used in FDTD and FDE.

Syntax

See also
delete

clearglobalvariable

Description
Clears the designated global variable.
Used in FDTD and FDE.

Syntax

See also
clearallglobalvariable

clearallglobalvariable

Description
Clears all the global variables.
Used in FDTD and FDE.

Syntax

See also
clearglobalvariable

Export

savedatafile

Description
Saves data to .mdf(MaxCloud Data File) file.
Used in FDTD and FDE.

Syntax

Example

b=[1,2];
jh=[3,4;5,7];
savedatafile('data', b, jh);

The .mdf file data.mdf will be saved in the work path.

See also
savematlabmatfile

savematlabmatfile

Description
Saves data to .mat (MATLAB-FILE) file.
Used in FDTD and FDE.

Syntax

Example

b=[1,2];
jh=[3,4;5,7];
savematlabmatfile('data',b,jh);

The .mat file data.mat will be saved in the work path.

See also
loadmatlabmatfile

saveproject

Description
Saves the project file according to the file path.
Used in FDTD and FDE.

Syntax

Example

saveproject('F:\projects\new_project.mpps');

See also
loadproject

saveh5file

Description

Saves data to h5df file.

Used in FDTD and FDE.

Syntax

Example

Saves variables to h5df file.

file_path = 'D:\H5\example.h5';

a = 1; 
b = 'str';

# save variables a and b to the h5df file named example.h5
saveh5file( file_path, a, b );

See also

loadh5file

saveascii

Description
Saves data to .mdfascii (MaxCloud Data File by Ascii) file.
Used in FDTD and FDE.

Syntax

Example

b=[1,2];
jh=[3,4;5,7];
saveascii('data',b,jh);

The .mdfascii file data.mdfascii will be saved in the work path.

See also
loadascii

fprintf

Description
Formatted printing to a file.
Used in FDTD and FDE.

Syntax

The RLaB fprintf is a limited feature version of the C-language fprintf. The features are limited because RLaB does not support all of the data types the C-language does.

• file_num
  The 1st argument determines the file to which the output is sent. The file_num can be generated by fopen function.

• format_string
  A valid fprintf format string such as "%d".

• var_1, var_2, ...
  The var_1, var_2, ... are any number of constants or variables that match the format string. fprintf cannot print out vector, matrix, cell, struct objects as a whole. Valid print objects are strings, constants, and scalars.

Example

# write the string "str" into file "stdout.txt"

# open the file before writing
f = fopen("stdout.txt", "w+"); 

fprintf(f, "%s, %s", "Hello", "world!");

See also
printf, sprintf, write, read

fwrite

Description
Binary stream output.
Used in FDTD and FDE.

Syntax

See also
fread, fseek, close, open, write

format

Description
Sets the printing format.
Used in FDTD and FDE.

format sets the output print format for all numeric output. If no arguments are supplied, then the output print formats are reset to the default values.

Syntax

The meanings of the input parameters are as follows:

• PRECISION
  Represents the precision with which numbers will be printed. For instance, if PRECISION has a value of 4, then 4 significant digits will be printed for numeric values.

• WIDTH
  Represents the minimum field width of the formatted output.

format returns a 2-element matrix containing the previous width and precision values. Subsequently, this matrix can be used to reset format.

Example
Example 1:

123456789.123456789
format(10);
123456789.123456789

Result:

val =
   123456789
val =
 123456789.1

Example 2:

format();
a = rand(3,3) 
format(10);
a
format(15,10);
a

Result:

a =
       0.57      0.831      0.462
      0.683     0.0735      0.435
      0.396      0.464       0.63
a =
   0.5701993108   0.8312915564   0.4622091651
   0.6828844547  0.07354432344   0.4351293147
   0.3963157833   0.4644346535   0.6302834153
a =
     0.5701993108     0.8312915564     0.4622091651
     0.6828844547    0.07354432344     0.4351293147
     0.3963157833     0.4644346535     0.6302834153

printf

Description
The RLaB printf is a limited feature version of the C-language printf().
Used in FDTD and FDE.

The features are limited because RLaB does not support all of the data type the C-language does.

Syntax

The meanings of the input parameters are as follows:

• formatstring
  This parameter must be a valid printf format string.
• VARi
  VARi are any number of constants or variables that match the format string. printf cannot print out vector, matrix, or struct objects as a whole. Valid print objects are strings, constants, and scalars.

Example

The following shows how one might print out the annotated contents of a matrix.

a = rand(2,3);
a_size = size(a);

for(i = 1 : a_size(1))
 
  for(j = 1 : a_size(2))
  
    printf("a[%i;%i] = %f\n", i, j, a[i,j]);
  end
end

Result:

a[1;1] = 0.110975
a[1;2] = 0.773031
a[1;3] = 0.131552
a[2;1] = 0.699178
a[2;2] = 0.956544
a[2;3] = 0.228156

However, it would be more efficient to use:

print(a);

See also
fprintf, sprintf, write, read

write

Description
Writes a string to the file and adds a newline.
Used in FDTD and FDE.

Syntax

See also
writem

writem

Description
Writes the matrix data to the file in designated format.
Used in FDTD and FDE.

writem is the counterpart to readm. writem writes the matrix data to the file denoted by the 1st argument in a generic format.

The format used is:

line 1:     value[1;1]     ...  value[1;ncol] \n
...
line nrow:  value[nrow;1]  ...  value[nrow;ncol] \n

writem will write real and complex numeric matrices, as well as string matrices even though readm can only read real numeric matrices. Complex matrices are written as a single 2*nrow by ncolumn real matrix. Sparse matrices are written as triplets (row column value) for each element of the matrix.

writem does not close the file after writing A. The file is left open for further writes if necessary. fclose can be called to explicitly close the file.

Syntax

Example

a = [1, 2, 3];
writem("stdout.txt", a)
fclose("stdout.txt")

See also
fclose, getline, open, readm, write

writeascii

Description
Writes object(s) to file in ASCII format.
Used in FDTD and FDE.

The writeascii function takes at least two arguments. The 1st argument is the string that identifies the file to write to. The file is opened with write permission, destroying any pre-existing contents. The file is left open so that subsequent writes will append to the file, and not destroy the contents.

The arguments after the file name are the objects that will be written. All objects are written in RLaB ASCII format.

Syntax

Example

writeascii( 'filename', a , b , c );

The above code will open the file named filename in write mode, and write the contents of the variables a, b, and c.

See also
close, read, readascii

spwrite

Description
Writes sparse matrix to the designated file.
Used in FDTD and FDE.

The spwrite function takes at least two arguments. The 1st argument is the string that identifies the file to write to. The file is opened with write permission, destroying any pre-existing contents. The file closed after the matrix is written.

The default format for the sparse matrix is the internal storage format: compressed row-wise storage. See the Rlab Reference Manual for more explanation of this storage format.

A third, and optional argument, is a string specifying either the default, or an optional output format. The value of the string can be either 'sparse' (default) or 'graph'. The graph output is a file suitable for use with the Metis or Chaco graph partitioning/re-ordering software.

Syntax

See also
write

sprintf

Description
Formatted printing to a string.
Used in FDTD and FDE.

The RLaB sprintf is a limited feature version of the C-language sprintf.
The features are limited because RLaB does not support all of the data types the C-language does.

Syntax

The meanings of the input parameters are as follows:

• stringvar
  The output of sprintf is written to this variable.
• formatstr
  A valid sprintf format string.
• VARi
  Are any number of constants or variables that match the format string. sprintf cannot print out vector, matrix, or struct objects as a whole. Valid print objects are strings, constants, and scalars.

See also
printf, fprintf, write, read

Import

loaddatafile

Description
Loads MaxCloud Data (.mdf data) into workspace.
Used in FDTD and FDE.

Syntax

Example

# The data in data.mdf will be loaded into workspace.
loaddatafile('data.mdf');
 
var = struct();
# The data in data.mdf will be packaged into a struct variable and assigned to var.
loaddatafile('data.mdf',var);

loadmatlabmatfile

Description
Loads the data in the designated .mat file into workspace.
Used in FDTD and FDE.

Syntax

Example

# The data in data.mat will be loaded into workspace.
loadmatlabmatfile('data.mat');
 
# The data in data.mat will be packaged into a struct variable and assigned to var.
var = struct();
loadmatlabmatfile('data.mat', var);
 

loadproject

Description
Loads a project file according to the file path.
Used in FDTD and FDE.

Syntax

Example

loadproject('F:\projects\new_project.mpps');

See also
saveproject

loadh5file

Description

Imports the specific h5df file.

Used in FDTD and FDE.

Syntax

Example

Import data in h5df file.

file_path = 'D:\H5\example.h5';

loadh5file( file_path );

See also

saveh5file

loadascii

Description
Loads data in specified .mdfascii file into workspace.
Used in FDTD and FDE.

Syntax

Example

# The data in data.mdfascii will be loaded into workspace.
loadascii('data.mdfascii');
 
# The data in data.mdfascii will be packaged into a struct variable and assigned to var.
var = struct();
loadascii('data.mdfascii',var);

See also
saveascii

fopen

Description
Opens the designated file.
Used in FDTD and FDE.

Syntax

The fopen functions allows user to specify the file access mode. The allowed file access modes are as follows:

See also
fclose

fclose

Description
Closes the designated file.
Used in FDTD and FDE.

Syntax

See also
fread

fread

Description
Reads specified number of data in the designated type from the designated file and returns the result in a numeric matrix.
Used in FDTD and FDE.

Syntax

The meanings of the input parameters are as follows:

• NITEMS
  Number of objects of type TYPE to read from file named FILENAME. If NITEMS is inf(), then fread will read from the file named FILENAME until end-of-file is reached.

• TYPE
  'char'
  'unsigned char'
  'short int'
  'unsigned int'
  'int'
  'float'
  'double'

• SWAPB
  0 Do not swap bytes in a word (default).
  1 Do swap the bytes in each word.

See also
fseek, fwrite, close, open, write

readm

Description
Reads ASCII matrix from a file.
Used in FDTD and FDE.

readm reads a generic matrix of data from the file denoted by the string argument FILENAME. The return value is the newly created matrix. The second, and optional, argument is a two-element matrix that specifies the size of the matrix to read.

If the matrix size is not specified, then the matrix is filled row-wise with the input data. Otherwise (if the size is specified), the matrix is filled column-wise, as the input is read.

The file format is generic ASCII. The rows of the matrix are separated by newlines, and the columns are separated by whitespace. Unnecessary newlines, either before, or after the data will confuse readm, and will probably result in an error message. Only one matrix can be stored in a file. If you need to store more than one matrix in a file, use write, and read.

readm can only read in numeric matrices. The result of reading in string matrices is undefined.

Syntax

Example

1 2 3 4
5 6 7 8
9 10 11 12

The above values in a file called 'test' would be read in like:

 > a = readm('test')
 a =
 matrix columns 1 thru 4
        1          2          3          4  
        5          6          7          8  
        9         10         11         12 

readm exists to read in data from other programs. In many cases a simple awk script will filter the other programs output into one or more columns of data. readm will read the data into the matrix, then the matrix can be reshaped if necessary.

Notes:
readm has no idea how many rows are in the matrix it is reading. This is because readm can work with pipes and process output where it gets the matrix as a stream. readm uses a heuristic to guess how many rows of the matrix to allocate at one time. A second, optional argument, [NR, NC] can be specified if the heuristic does not yield the performance you desire. The heuristic is purposely memory conservative.

readm ( 'filename' , [NR, NC] )

See also
reshape, getline, open, read, writem

rfile

Description
Loads an rfile.
Used in FDTD and FDE.

Syntax

rfile name loads the contents of the file denoted by name into the workspace. The name argument is NOT a string, and does not have to include the '.r' suffix.

Allowable names for rfiles are filenames that start with a digit or a letter (a-z or A-Z) and contain digits, letters, hyphens(-), and underscores(_).
You may not be able to use all the possible filenames allowed by the host operating system.

If the user's environment does not contain RLAB2_PATH, then the default search-path is used. The default is set at compile time. Normally the default is '.', the current working directory.
rfile is a command, not an expression or statement. Therefore, it must be issued on a line by itself, and cannot occur in the midst of another statement or expression. The rfile command cannot be continued across lines (no continuations).
The command rfile name can be used more than once. Each time the command is issued the file name.r is loaded.
The rfile command tries to be friendly. If you give it a string without the '.r' extension, it will automatically add one for you. If you give it a string with the '.r' extension, it will leave it alone.
The contents of the named file can be any valid RLaB commands or functions. There is no limit to the number of functions that a file can contain. Additionally, a mixture of commands, and function definitions can be included in the same file.

Example

rfile roots.r poly bode 

See also
load

readascii

Description
readascii reads the file identified by the FILENAME. The file is opened with read access, and all of the contents are read. The file identified by the 1st argument must contain data that is in RLaB ASCII format. The entities in the file are installed in the global symbol table, overwriting any existing entities. Upon completion the file is closed.
Used in FDTD and FDE.

Syntax

Example
Reads ASCII data from the file named bunch_of_data_in_a_file.

readascii ('bunch_of_data_in_a_file');    

The second form of the function allows the data in the file to be read into struct variable X. The global-symbol-table is untouched (except for X).

 readascii ('bunch_of_data', X); 

The contents of the file bunch_of_data are read and stored in the struct variable X. Except for the creation/modification of the variable X, the global-symbol-table is unchanged.

See also
close, getline, read, readm, writem, writeascii

readb

Description
Reads designated file in binary mode.
Used in FDTD and FDE.

Syntax

See also
readascii

readgraph

Description
Reads graph data from designated file.
Used in FDTD and FDE.

Syntax

The correct format of the file read by readgraph function is as follows:

num_vertices(number of vertices) num_edge(number of edges)
adjacent vertex indexes of the first vertex:   a11 a12 … 
adjacent vertex indexes of the second vertex:  a21 a22 …
…

The following is a correct instance:

3 2
2 3
1
1

See also
readb