The Current Directory. Initially,
the
only directory
that
exists is
the
built-in directory HOME. After creating
other
directories, you
can
choose
which
is
the
current
directory-that
is,
which
set
of
variables
appears
in
the
USER
menu.
To
choose
the
current
directory you evaluate its
name-for
example,
if
you've
just created a directory, you
make
it
the
current
directory
by
pressing
the
appropriate
key in
the
USER
menu.
Almost all
commands
that
use variables work only in
the
current
di-
rectory, since
the
purpose
of
multiple directories is to control
which
variables are available.
You
can alter a variable only if it's in
the
cur-
rent
directory.
The following
commands
in
the
MEMORY
menu
act
on
the
current
directory.
Command
Description
VARS
Returns a list
of
names
of
all variables
and
directories in
the
current
directory.
ORDER
CLUSR
Reorders variables
and
directories in
the
current
direc-
tory as specified
by
a list.
Purges
all variables
and
empty
directories in
the
current
directory.
The Current Path.
You
can
check
where
you
are
in
the
directory
structure
by
executing
the
command
PATH. It
returns
a list specifying
the
sequence
of
directories from
the
HOME directory to
the
current
directory.
In some cases
the
calculator searches
not
only
the
current
directory,
but
the
entire
current
path.
The search begins in
the
current
directory;
if
the
variable
isn't
found,
the
search
continues
in
the
parent
direc-
tory;
and
this process
continues
back to
the
HOME directory.
This occurs in
the
evaluation
of
names-after
all, you
could
never
re-
turn
to a
parent
directory if you
couldn't
successfully evaluate its
name. Evaluation
of
names
occurs
when
you key in
an
unquoted
name,
when
you plot
or
use
the
Solver,
when
you evaluate algebraics
on
the
stack,
and
so on.
184
20:
Memory
To Next Page
Loading...
