Function: _def_output
Class: default
Section: default
C-Name: sd_output
Prototype:
Help:
Doc: there are three possible values: 0
 (=~\var{raw}), 1 (=~\var{prettymatrix}), or 3
 (=~\var{external} \var{prettyprint}). This
 means that, independently of the default \kbd{format} for reals which we
 explained above, you can print results in three ways:

 \item \tev{raw format}, i.e.~a format which is equivalent to what you
 input, including explicit multiplication signs, and everything typed on a
 line instead of two dimensional boxes. This can have several advantages, for
 instance it allows you to pick the result with a mouse or an editor, and to
 paste it somewhere else.

 \item \tev{prettymatrix format}: this is identical to raw format, except
 that matrices are printed as boxes instead of horizontally. This is
 prettier, but takes more space and cannot be used for input. Column vectors
 are still printed horizontally.

 \item \tev{external prettyprint}: pipes all \kbd{gp}
 output in TeX format to an external prettyprinter, according to the value of
 \tet{prettyprinter}. The default script (\tet{tex2mail}) converts its input
 to readable two-dimensional text.

 Independently of the setting of this default, an object can be printed
 in any of the three formats at any time using the commands \b{a} and \b{m}
 and \b{B} respectively.

 The default value is \kbd{1} (\var{prettymatrix}).
