subscripted variables

subscripted variables

It is common in mathematics to use subscripted variables. We use the underscore to represent subscripts. If we haven't assigned a value to x we may simply start using it as a subscripted variable. The subscripts can be anything.

i1 : x



o1 = x



o1 : Symbol

i2 : x_4



o2 = x

      4



o2 : IndexedVariable

i3 : x_(2,3)



o3 = x

      2,3



o3 : IndexedVariable

The .. operator knows what to do with subscripted variables.

i4 : x_10 .. x_20



o4 = (x  , x  , x  , x  , x  , x  , x  , x  , x  , x  , x  )

       10   11   12   13   14   15   16   17   18   19   20



o4 : Sequence

i5 : x_(1,1) .. x_(2,3)



o5 = (x   , x   , x   , x   , x   , x   )

       1,1   1,2   1,3   2,1   2,2   2,3



o5 : Sequence

Values can be assigned to these variables with #.

i6 : x#10 = 555;

i7 : x_10



o7 = 555

Be careful not to assign a value to x itself if you wish to continue using it as a subscripted variable.

See also:

IndexedVariable -- the class of all indexed variables

IndexedVariableTable -- the class of indexed variable tables