Labelled indices on arrays



Je la 03/05/2012 14:53, Jaime Villate skribis:
> On 05/03/2012 02:50 PM, Jaime Villate wrote:
>> On 05/03/2012 12:32 PM, maxima at peutch.e4ward.com wrote:
>>> I would like to create variables for each of the 2x2 possible states of
>>> my model. Along the first dimension, the state is either a or b. Along
>>> the second: x or y.
>>>
>>> I started by creating manually:
>>>     variable_ax: 1;
>>>     variable_ay: 33;
>>>     variable_bx: 4;
>>>     variable_by: 50;
>>>
>>> What I would like to do is something like being able to assign:
>>>     variable['a]['x] : 1;
>>>     variable['a]['y] : 33;
>>>
>>> and so on. But i get an error (assignment: cannot assign to
>>> (variable['a])['x]).
>> (%i2) concat('variable_,'a,'x) :: 1;
>> (%o2)  1
>> (%i3) concat('variable_,'a,'y) :: 33;
>> (%o3)  33
>> (%i4) variable_ax;
>> (%o4)  1
>> (%i5) variable_ay;
>> (%o5)  33
> I forgot to paste:
> 
> (%i6) ''(concat('variable_,'a,'x));
> (%o8) 1
> 
> Jaime
> 
> 

Thanks! Does that mean that there is no solution with arrays?