### 9.4 Summary of Built-in Variables

Here is a summary of all of Octave's built-in variables along with cross references to additional information and their default values. In the following table octave-home stands for the root directory where all of Octave is installed (the default is `/usr/local`, version stands for the Octave version number (for example, 2.1.x) and arch stands for the type of system for which Octave was compiled (for example, `i586-pc-linux-gnu`).

`DEFAULT_LOADPATH`
  See Function Files.

  Default value: `".:`octave-home`/lib/`version`"`.

`EDITOR`
  See Commands For History.

  Default value: `"emacs"`.

`EXEC_PATH`
  See Controlling Subprocesses.

  Default value: `":$PATH"`.

`INFO_FILE`
  See Getting Help.

  Default value: `"`octave-home`/info/octave.info"`.

`INFO_PROGRAM`
  See Getting Help.

  Default value: `"`octave-home`/libexec/octave/`version`/exec/`arch`/info"`.

`LOADPATH`
  See Function Files.

  Default value: `":"`, which tells Octave to use the directories specified by the built-in variable `DEFAULT_LOADPATH`.

`OCTAVE_HOME`
  Default value: `"/usr/local"`.
`PAGER`
  See Input and Output.

  Default value: `"less", or "more"`.

`PS1`
  See Customizing the Prompt.

  Default value: `"\s:\#> "`.

`PS2`
  See Customizing the Prompt.

  Default value: `"> "`.

`PS4`
  See Customizing the Prompt.

  Default value: `"+ "`.

`automatic_replot`
  See Two-Dimensional Plotting.

  Default value: 0.

`beep_on_error`
  See Error Handling.

  Default value: 0.

`completion_append_char`
  See Commands For Completion.

  Default value: `" "`.

`default_save_format`
  See Simple File I/O.

  Default value: `"ascii"`.

`crash_dumps_octave_core`
  See Simple File I/O.

  Default value: 1.

`fixed_point_format`
  See Matrices.

  Default value: 0.

`gnuplot_binary`
  See Three-Dimensional Plotting.

  Default value: `"gnuplot"`.

`history_file`
  See Commands For History.

  Default value: `"~/.octave_hist"`.

`history_size`
  See Commands For History.

  Default value: 1024.

`ignore_function_time_stamp`
  See Function Files.

  Default value: `"system"`.

`max_recursion_depth`
  See Recursion.

  Default value: 256.

`output_max_field_width`
  See Matrices.

  Default value: 10.

`output_precision`
  See Matrices.

  Default value: 5.

`page_screen_output`
  See Input and Output.

  Default value: 1.

`print_answer_id_name`
  See Terminal Output.

  Default value: 1.

`print_empty_dimensions`
  See Empty Matrices.

  Default value: 1.

`return_last_computed_value`
  See Returning From a Function.

  Default value: 0.

`save_precision`
  See Simple File I/O.

  Default value: 17.

`saving_history`
  See Commands For History.

  Default value: 1.

`sighup_dumps_octave_core`
  See Simple File I/O.

  Default value: 1.

`sigterm_dumps_octave_core`
  See Simple File I/O.

  Default value: 1.

`silent_functions`
  See Defining Functions.

  Default value: 0.

`split_long_rows`
  See Matrices.

  Default value: 1.

`struct_levels_to_print`
  See Data Structures.

  Default value: 2.

`suppress_verbose_help_message`
  See Getting Help.

  Default value: 1.

`warn_assign_as_truth_value`
  See The if Statement.

  Default value: 1.

`warn_comma_in_global_decl`
  See Global Variables.

  Default value: 1.

`warn_divide_by_zero`
  See Arithmetic Ops.

  Default value: 1.

`warn_empty_list_elements`
  See Empty Matrices.

  Default value: 0.

`warn_fortran_indexing`
  See Index Expressions.

  Default value: 0.

`warn_function_name_clash`
  See Function Files.

  Default value: 1.

`warn_imag_to_real`
  See Special Utility Matrices.

  Default value: 0.

`warn_missing_semicolon`
  See Defining Functions.

  Default value: 0.

`warn_neg_dim_as_zero`
  See Special Utility Matrices.

  Default value: 0.

`warn_num_to_str`
  See String Conversions.

  Default value: 1.

`warn_reload_forces_clear`
  See Dynamically Linked Functions.

  Default value: 1.

`warn_resize_on_range_error`
  See Index Expressions.

  Default value: 0.

`warn_separator_insert`
  See Matrices.

  Default value: 0.

`warn_single_quote_string`
  See String Conversions.

  Default value: 0.

`warn_str_to_num`
  See String Conversions.

  Default value: 0.

`warn_undefined_return_values`
  See Multiple Return Values.

  Default value: 0.

`warn_variable_switch_label`
  See The switch Statement.

  Default value: 0.