The Fortress Language Specification - CiteSeerX

A = [1 2 3; 4 5 6; 7 8 9]
then A 1,0 evaluates to 4 .
An array of two dimensions whose elements are a subtype of Number can be coerced to a matrix. Matrix types
are written MatrixT[n 0 × . . . × n k−1 ] , where k > 1. A type of this form can be abbreviated as T n 0×...×n k−1
.
Matrices are indexed in the same manner as arrays.
A one-dimensional array whose elements are a subtype of Number can be coerced to a vector. Vector types are written
VectorT[n] . A type of this form can be abbreviated as T n , unless T is declared in the enclosing scope to be a
physical dimension or unit.
The element expressions in an array expression may be either scalars or array expressions themselves. If an element is
an array expression, it is “flattened” (pasted) into the enclosing expression. This pasting works because arrays never
contain other arrays as elements. The elements along a row (or column) must have the same number of columns
(or rows), though two elements in different rows (columns) need not have the same number of columns (rows). See
Section 6.5 for a discussion of matrix unpasting.
The following four examples are all equivalent:
[3 4
5 6]
[3 4 ;
5 6 ]
Here is a 3 × 3 × 3 × 2 matrix example:
[1 0 0
0 1 0
0 0 1 ; ; 0 1 0
1 0 1
0 1 0 ; ; 1 0 1
0 1 0
1 0 1
; ; ;
1 0 0
0 1 0
0 0 1 ; ; 0 1 0
1 0 1
0 1 0 ; ; 1 0 1
0 1 0
1 0 1 ]
[ 3 4
; 5 6 ]
[3 4 ; 5 6]
Tuple Expressions:
Syntax:
Aggregate ::= (Expr( , Expr) + )
| ([Expr( , Expr) ∗ , ] Expr ... )
| ([Expr( , Expr) ∗ , ] [Expr ... , ] Id = Expr ( , Id = Expr) ∗ )
Tuple element expressions are enclosed in parentheses and separated by commas. Each element is one of:
• A plain expression “ e ”
• A varargs expression “e...”
• A keyword-value pair “identifier = e ”
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