Overhaul interp1, interp2, interp3 functions. * NEWS: Announce change in 'cubic' interpolation method for interp2 to match Matlab. * bicubic.m: Use interp2 (..., "spline") in %!tests. * interp1.m: Improve docstring. Use switch statement instead of if/elseif tree for simpler code. Use more informative error message than 'table too short'. Add titles to demo plots. Add new demo block showing difference between 'pchip' and 'spline' methods. * interp2.m: Rewrite docstring. Use variable 'extrap' instead of 'extrapval' to match documentation. Use clearer messages in error() calls. Make 'cubic' use the same algorithm as 'pchip' for Matlab compatibility. Use Octave coding conventions regarding spaces between variable and parenthesis. Added input validation tests. * interp3.m: Rewrite docstring. Use clearer messages in error() calls. Make 'cubic' use the same algorithm as 'pchip' for Matlab compatibility. Simplify input processing. Rewrite some %!tests for clarity. Added input validation tests.

## System-wide startup file for Octave.
##
## This file should contain any commands that should be executed each
## time Octave starts for every user at this site.

## Configure readline using the file inputrc in the Octave startup
## directory.

readline_read_init_file (sprintf ("%s%s%s",
                                  octave_config_info ("startupfiledir"),
                                  filesep, "inputrc"));

if (strcmp (PAGER (), "less") && isempty (getenv ("LESS")))
  PAGER_FLAGS ('-e -X -P"-- less ?pB(%pB\\%):--. (f)orward, (b)ack, (q)uit$"');
endif

## This appears here instead of in the pkg/PKG_ADD file so that --norc
## will also skip automatic loading of packages.

pkg ("load", "auto");

atexit ("__finish__");