A brief introduction

Dot mode can be entered one line at a time, by starting the line with a period . followed by a space:

% <ring 3 a-z r
% type r
a b c 
% . betti res type `dsum r r
a b c 0 0 0 
0 0 0 a b c 
0.1...
computation complete after degree 1
total:      2     6     6     2 
--------------------------------
    0:      2     6     6     2

The save operator ` prevents the argument to type from being thrown out, so it can be reused as an argument to res.

Alternatively, dot mode can be toggled on and off by a lone dot on a line; the prompt changes from % to .% to indicate the mode:

% .
.% betti res dsum r r
0.1...
computation complete after degree 1
total:      2     6     6     2 
--------------------------------
    0:      2     6     6     2

The interface mode is an attribute of each input file, and each file starts out not in dot mode. The mode of a given input file is restored as expected, after Macaulay finishes reading other files opened by that file. The dot processor is re-entrant, so it can be used while a computation is interrupted, without disturbing the remaining evaluation of the expression that created the computation. (A user shouldn't have to think about such issues; if you run into an unexpected problem of this nature, please let us know.)

An expression syntax is supported for manipulating matrices and integers ( is a transpose operator):

.% type s = r * \r
a2+b2+c2 
.% type n = 1 + col_degree s 1
3