Hello, list. I need to create the 4x4 matrix, a upper-left element of
which has indices [0,0].
The genmatrix(a,3,3,0,0) command gives such matrix, but to call the
element of this matrix one needs to use indices from 1 to 4.( for
instance, to call the element "a_00" in example below one needs to type
"a[1,1];")
Is it possible to create an matrix, the upper-left element of which can
be called by a[0,0]?
(%i1) a:genmatrix(a,3,3,0,0);
[ a a a a ]
[ 0, 0 0, 1 0, 2 0, 3 ]
[ ]
[ a a a a ]
[ 1, 0 1, 1 1, 2 1, 3 ]
(%o1) [ ]
[ a a a a ]
[ 2, 0 2, 1 2, 2 2, 3 ]
[ ]
[ a a a a ]
[ 3, 0 3, 1 3, 2 3, 3 ]
(%i2) a[0,0];
apply: no such matrix element: [0, 0]
-- an error. To debug this try: debugmode(true);
(%i3) a[1,1];
(%o3) a
0, 0
*********************************************************************************
You can use the array
For example:
(%i1) array(a,3,3);
(%o1) a
(%i2) a[0,0]; a[1,0];a[3,3];
(%o2) a[0,0]
(%o3) a[1,0]
(%o4) a[3,3]
(%i5) a[4,4];
Array a has dimensions [3,3], but was called with [4,4]
-- an error. To debug this try: debugmode(true);
(%i6) fillarray (a, makelist (i, i, 1, 16));
(%o6) a
(%i7) a[0,0];
(%o7) 1
(%i8) a[3,3];
(%o8) 16
(%i9) a[3,3]:100;
(%o9) 100
(%i10) a[3,3];
(%o10) 100
AD