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Re: Information about subscripted function

In article <cq8tj5$h18$1 at>, seb at wrote:

> when I define a function with a subscript in its
> name: (cell content below)
> In[1]:= \!\(f\_1[x_] := x^2\)
> I can't see it by use of information operator:
> In[2]:= \!\(\(?\ f\_1\)\)
> Information::ssym
> Out[2]:= \!\(Information[f\_1, LongForm -> False]\)
> of course I may ask:
> In[3]:= ? Subscript
> but then I get ALL functions which have subscripts in their names!
> so, how to ask about the defintions of subscripted functions ?

By default, the definition is associated with Subscript, not with f. In 
InputForm, your first input reads

  Subscript[f, 1][x_] := x^2

and so you can see why this is so. 

You could use Symbolize in the


package to symbolize Subscript[f, 1] and then it will work.

Alternatively, you could use association. However, you cannot associate 
the definition with f using

  f /: Subscript[f, 1][x_] := x^2

However, you can achieve what you want using pure functions:

 f /: Subscript[f, 1] := Function[x, x^2]



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School of Physics, M013                         Fax: +61 8 6488 1014
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