Commands for controlling vector and matrix display use the `v` prefix
instead of the usual `d` prefix. But they are display modes; in
particular, they are influenced by the `I` and `H` prefix keys
in the same way (see Display Modes). Matrix display is also
influenced by the `d O` (`calc-flat-language`

) mode;
see Normal Language Modes.

The commands `v <` (`calc-matrix-left-justify`

), `v >`
(`calc-matrix-right-justify`

), and `v =`
(`calc-matrix-center-justify`

) control whether matrix elements
are justified to the left, right, or center of their columns.

The `v [` (`calc-vector-brackets`

) command turns the square
brackets that surround vectors and matrices displayed in the stack on
and off. The `v {` (`calc-vector-braces`

) and `v (`
(`calc-vector-parens`

) commands use curly braces or parentheses,
respectively, instead of square brackets. For example, `v {` might
be used in preparation for yanking a matrix into a buffer running
Mathematica. (In fact, the Mathematica language mode uses this mode;
see Mathematica Language Mode.) Note that, regardless of the
display mode, either brackets or braces may be used to enter vectors,
and parentheses may never be used for this purpose.

The `v ]` (`calc-matrix-brackets`

) command controls the
“big” style display of matrices, for matrices which have more than
one row. It prompts for a string of code letters; currently
implemented letters are `R`

, which enables brackets on each row
of the matrix; `O`

, which enables outer brackets in opposite
corners of the matrix; and `C`

, which enables commas or
semicolons at the ends of all rows but the last. The default format
is ‘`RO`’. (Before Calc 2.00, the format was fixed at ‘`ROC`’.)
Here are some example matrices:

[ [ 123, 0, 0 ] [ [ 123, 0, 0 ], [ 0, 123, 0 ] [ 0, 123, 0 ], [ 0, 0, 123 ] ] [ 0, 0, 123 ] ] RO ROC

[ 123, 0, 0 [ 123, 0, 0 ; 0, 123, 0 0, 123, 0 ; 0, 0, 123 ] 0, 0, 123 ] O OC

```
[ 123, 0, 0 ] 123, 0, 0
[ 0, 123, 0 ] 0, 123, 0
[ 0, 0, 123 ] 0, 0, 123
R blank
```

Note that of the formats shown here, ‘`RO`’, ‘`ROC`’, and
‘`OC`’ are all recognized as matrices during reading, while
the others are useful for display only.

The `v ,` (`calc-vector-commas`

) command turns commas on and
off in vector and matrix display.

In vectors of length one, and in all vectors when commas have been
turned off, Calc adds extra parentheses around formulas that might
otherwise be ambiguous. For example, ‘`[a b]`’ could be a vector
of the one formula ‘`a b`’, or it could be a vector of two
variables with commas turned off. Calc will display the former
case as ‘`[(a b)]`’. You can disable these extra parentheses
(to make the output less cluttered at the expense of allowing some
ambiguity) by adding the letter `P`

to the control string you
give to `v ]` (as described above).

The `v .` (`calc-full-vectors`

) command turns abbreviated
display of long vectors on and off. In this mode, vectors of six
or more elements, or matrices of six or more rows or columns, will
be displayed in an abbreviated form that displays only the first
three elements and the last element: ‘`[a, b, c, ..., z]`’.
When very large vectors are involved this will substantially
improve Calc’s display speed.

The `t .` (`calc-full-trail-vectors`

) command controls a
similar mode for recording vectors in the Trail. If you turn on
this mode, vectors of six or more elements and matrices of six or
more rows or columns will be abbreviated when they are put in the
Trail. The `t y` (`calc-trail-yank`

) command will be
unable to recover those vectors. If you are working with very
large vectors, this mode will improve the speed of all operations
that involve the trail.

The `v /` (`calc-break-vectors`

) command turns multi-line
vector display on and off. Normally, matrices are displayed with one
row per line but all other types of vectors are displayed in a single
line. This mode causes all vectors, whether matrices or not, to be
displayed with a single element per line. Sub-vectors within the
vectors will still use the normal linear form.