# matrix(n) 1.2.1 struct "Tcl Data Structures"

## NAME

matrix - Create and manipulate matrix objects

## SYNOPSIS

package require Tcl 8.2
package require struct ?1.2.1?

matrixName option ?arg arg ...?
matrixName add column ?values?
matrixName add row ?values?
matrixName add columns n
matrixName add rows n
matrixName cells
matrixName cellsize column row
matrixName columns
matrixName columnwidth column
matrixName delete column column
matrixName delete row row
matrixName destroy
matrixName format 2string ?report?
matrixName format 2chan ??report? channel?
matrixName get cell column row
matrixName get column column
matrixName get rect column_tl row_tl column_br row_br
matrixName get row row
matrixName insert column column ?values?
matrixName insert row row ?values?
matrixName link ?-transpose? arrayvar
matrixName rowheight row
matrixName rows
matrixName search ?-nocase? ?-exact|-glob|-regexp? all pattern
matrixName search ?-nocase? ?-exact|-glob|-regexp? column column pattern
matrixName search ?-nocase? ?-exact|-glob|-regexp? row row pattern
matrixName search ?-nocase? ?-exact|-glob|-regexp? rect column_tl row_tl column_br row_br pattern
matrixName set cell column row value
matrixName set column column values
matrixName set rect column row values
matrixName set row row values
matrixName swap columns column_a column_b
matrixName swap rows row_a row_b
matrixName unlink arrayvar

## DESCRIPTION

The ::struct::matrix command creates a new matrix object with an associated global Tcl command whose name is matrixName. This command may be used to invoke various operations on the matrix. It has the following general form:

matrixName option ?arg arg ...?
  Option and the args determine the exact behavior of the command.

A matrix is a rectangular collection of cells, i.e. organized in rows and columns. Each cell contains exactly one value of arbitrary form. The cells in the matrix are addressed by pairs of integer numbers, with the first (left) number in the pair specifying the column and the second (right) number specifying the row the cell is in. These indices are counted from 0 upward. The special non-numeric index end refers to the last row or column in the matrix, depending on the context. Indices of the form end-number are counted from the end of the row or column, like they are for standard Tcl lists. Trying to access non-existing cells causes an error.

The matrices here are created empty, i.e. they have neither rows nor columns. The user then has to add rows and columns as needed by his application. A specialty of this structure is the ability to export an array-view onto its contents. Such can be used by tkTable, for example, to link the matrix into the display.

The following commands are possible for matrix objects:

matrixName add column ?values?
  Extends the matrix by one column and then acts like setcolumn (see below) on this new column if there were values supplied. Without values the new cells will be set to the empty string. The new column is appended immediately behind the last existing column.
matrixName add row ?values?
  Extends the matrix by one row and then acts like setrow (see below) on this new row if there were values supplied. Without values the new cells will be set to the empty string. The new row is appended immediately behind the last existing row.
matrixName add columns n
  Extends the matrix by n columns. The new cells will be set to the empty string. The new columns are appended immediately behind the last existing column. A value of n equal to or smaller than 0 is not allowed.
matrixName add rows n
  Extends the matrix by n rows. The new cells will be set to the empty string. The new rows are appended immediately behind the last existing row. A value of n equal to or smaller than 0 is not allowed.
matrixName cells
  Returns the number of cells currently managed by the matrix. This is the product of rows and columns.
matrixName cellsize column row
  Returns the length of the string representation of the value currently contained in the addressed cell.
matrixName columns
  Returns the number of columns currently managed by the matrix.
matrixName columnwidth column
  Returns the length of the longest string representation of all the values currently contained in the cells of the addressed column if these are all spanning only one line. For cell values spanning multiple lines the length of their longest line goes into the computation.
matrixName delete column column
  Deletes the specified column from the matrix and shifts all columns with higher indices one index down.
matrixName delete row row
  Deletes the specified row from the matrix and shifts all row with higher indices one index down.
matrixName destroy
  Destroys the matrix, including its storage space and associated command.
matrixName format 2string ?report?
  Formats the matrix using the specified report object and returns the string containing the result of this operation. The report has to support the printmatrix method. If no report is specified the system will use an internal report definition to format the matrix.
matrixName format 2chan ??report? channel?
  Formats the matrix using the specified report object and writes the string containing the result of this operation into the channel. The report has to support the printmatrix2channel method. If no report is specified the system will use an internal report definition to format the matrix. If no channel is specified the system will use stdout.
matrixName get cell column row
  Returns the value currently contained in the cell identified by row and column index.
matrixName get column column
  Returns a list containing the values from all cells in the column identified by the index. The contents of the cell in row 0 are stored as the first element of this list.
matrixName get rect column_tl row_tl column_br row_br
  Returns a list of lists of cell values. The values stored in the result come from the sub-matrix whose top-left and bottom-right cells are specified by column_tl, row_tl and column_br, row_br resp. Note that the following equations have to be true: &quot;column_tl &lt;= column_br&quot; and &quot;row_tl &lt;= row_br&quot;. The result is organized as follows: The outer list is the list of rows, its elements are lists representing a single row. The row with the smallest index is the first element of the outer list. The elements of the row lists represent the selected cell values. The cell with the smallest index is the first element in each row list.
matrixName get row row
  Returns a list containing the values from all cells in the row identified by the index. The contents of the cell in column 0 are stored as the first element of this list.
matrixName insert column column ?values?
  Extends the matrix by one column and then acts like setcolumn (see below) on this new column if there were values supplied. Without values the new cells will be set to the empty string. The new column is inserted just before the column specified by the given index. This means, if column is less than or equal to zero, then the new column is inserted at the beginning of the matrix, before the first column. If column has the value end, or if it is greater than or equal to the number of columns in the matrix, then the new column is appended to the matrix, behind the last column. The old column at the chosen index and all columns with higher indices are shifted one index upward.
matrixName insert row row ?values?
  Extends the matrix by one row and then acts like setrow (see below) on this new row if there were values supplied. Without values the new cells will be set to the empty string. The new row is inserted just before the row specified by the given index. This means, if row is less than or equal to zero, then the new row is inserted at the beginning of the matrix, before the first row. If row has the value end, or if it is greater than or equal to the number of rows in the matrix, then the new row is appended to the matrix, behind the last row. The old row at that index and all rows with higher indices are shifted one index upward.
matrixName link ?-transpose? arrayvar
  Links the matrix to the specified array variable. This means that the contents of all cells in the matrix is stored in the array too, with all changes to the matrix propagated there too. The contents of the cell (column,row) is stored in the array using the key column,row. If the option -transpose is specified the key row,column will be used instead. It is possible to link the matrix to more than one array. Note that the link is bidirectional, i.e. changes to the array are mirrored in the matrix too.
matrixName rowheight row
  Returns the height of the specified row in lines. This is the highest number of lines spanned by a cell over all cells in the row.
matrixName rows
  Returns the number of rows currently managed by the matrix.
matrixName search ?-nocase? ?-exact|-glob|-regexp? all pattern
  Searches the whole matrix for cells matching the pattern and returns a list with all matches. Each item in the aforementioned list is a list itself and contains the column and row index of the matching cell, in this order. The results are ordered by column first and row second, both times in ascending order. This means that matches to the left and the top of the matrix come before matches to the right and down.
  The type of the pattern (string, glob, regular expression) is determined by the option after the search keyword. If no option is given it defaults to -exact.
  If the option -nocase is specified the search will be case-insensitive.
matrixName search ?-nocase? ?-exact|-glob|-regexp? column column pattern
  Like search all, but the search is restricted to the specified column.
matrixName search ?-nocase? ?-exact|-glob|-regexp? row row pattern
  Like search all, but the search is restricted to the specified row.
matrixName search ?-nocase? ?-exact|-glob|-regexp? rect column_tl row_tl column_br row_br pattern
  Like search all, but the search is restricted to the specified rectangular area of the matrix.
matrixName set cell column row value
  Sets the value in the cell identified by row and column index to the data in the third argument.
matrixName set column column values
  Sets the values in the cells identified by the column index to the elements of the list provided as the third argument. Each element of the list is assigned to one cell, with the first element going into the cell in row 0 and then upward. If there are less values in the list than there are rows the remaining rows are set to the empty string. If there are more values in the list than there are rows the superfluous elements are ignored. The matrix is not extended by this operation.
matrixName set rect column row values
  Takes a list of lists of cell values and writes them into the submatrix whose top-left cell is specified by the two indices. If the sublists of the outerlist are not of equal length the shorter sublists will be filled with empty strings to the length of the longest sublist. If the submatrix specified by the top-left cell and the number of rows and columns in the values extends beyond the matrix we are modifying the over-extending parts of the values are ignored, i.e. essentially cut off. This subcommand expects its input in the format as returned by getrect.
matrixName set row row values
  Sets the values in the cells identified by the row index to the elements of the list provided as the third argument. Each element of the list is assigned to one cell, with the first element going into the cell in column 0 and then upward. If there are less values in the list than there are columns the remaining columns are set to the empty string. If there are more values in the list than there are columns the superfluous elements are ignored. The matrix is not extended by this operation.
matrixName swap columns column_a column_b
  Swaps the contents of the two specified columns.
matrixName swap rows row_a row_b
  Swaps the contents of the two specified rows.
matrixName unlink arrayvar
  Removes the link between the matrix and the specified arrayvariable, if there is one.

## EXAMPLES

The examples below assume a 5x5 matrix M with the first row containing the values 1 to 5, with 1 in the top-left cell. Each other row contains the contents of the row above it, rotated by one cell to the right.

     % M getrect 0 0 4 4
     {{1 2 3 4 5} {5 1 2 3 4} {4 5 1 2 3} {3 4 5 1 2} {2 3 4 5 1}}

     % M setrect 1 1 {{0 0 0} {0 0 0} {0 0 0}}
     % M getrect 0 0 4 4
     {{1 2 3 4 5} {5 0 0 0 4} {4 0 0 0 3} {3 0 0 0 2} {2 3 4 5 1}}

Assuming that the style definitions in the example section of the manpage for the package report are loaded into the interpreter now an example which formats a matrix into a tabular report. The code filling the matrix with data is not shown. contains useful data.

        % ::struct::matrix m
        % # ... fill m with data, assume 5 columns
        % ::report::report r 5 style captionedtable 1
        % m format 2string r
        +---+-------------------+-------+-------+--------+
        |000|VERSIONS:          |2:8.4a3|1:8.4a3|1:8.4a3%|
        +---+-------------------+-------+-------+--------+
        |001|CATCH return ok    |7      |13     |53.85   |
        |002|CATCH return error |68     |91     |74.73   |
        |003|CATCH no catch used|7      |14     |50.00   |
        |004|IF if true numeric |12     |33     |36.36   |
        |005|IF elseif          |15     |47     |31.91   |
        |   |true numeric       |       |       |        |
        +---+-------------------+-------+-------+--------+
        %
        % # alternate way of doing the above
        % r printmatrix m

## KEYWORDS

matrix