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From: Carl K. Woll on 11 Jun 2010 07:58
On 6/11/2010 2:09 AM, telefunkenvf14 wrote:
> Group:
>
> My goal is to generate a list of symbolic parameters that other
> functions in a package can Map[] over. For sake of example, suppose I
> define the following 'utility' function as part of a larger package.
>
> In[1]:= ClearAll["Global`*"]
> In[2]:= shares[n_?IntegerQ/;n>0,s_Symbol:
> s]:=Module[{i},Table[Symbol[ToString[s]<>ToString[i]],{i,n}]]
> In[3]:= shares[2]
>
> Out[3]= {s1,s2}
>
> I would now like to include the attribute Constant to each of the
> s1, ..., sn generated. What is the best way to do this?
> My gut tells me that ideally I'd want to do this inside the shares[]
> function itself, but I couldn't figure out how. The workaround I've
> been toying with is to define another utility function:
>
> In[4]:= setConstants[vars_]:=SetAttributes[#,Constant]&@vars
>
> This seems to work ok...But does anyone see potential pitfalls with
> this approach?
>
> In[5]:= setConstants[shares[2]]
> In[6]:= Attributes[s1]
> In[7]:= Attributes[s2]
>
> Out[6]= {Constant}
> Out[7]= {Constant}
>
> -RG
>
>

If the symbol you are creating already has a value, then SetAttributes
won't work.

Do the symbols need to always start with 1? If not, then using something
like:

Table[ Unique["s", Constant], {10}]

might be a possibility.

Carl Woll
Wolfram Research

From: Bob Hanlon on 11 Jun 2010 07:58

shares[n_Integer?Positive, s_Symbol: s] :=
Module[{var},
var = Table[
Symbol[ToString[s] <> ToString[i]],
{i, n}];
SetAttributes[#, Constant] & /@ var;
var]

shares[3]

{s1,s2,s3}

Attributes /@ %

{{Constant}, {Constant}, {Constant}}


Bob Hanlon

---- telefunkenvf14 <rgorka(a)gmail.com> wrote:

=============
Group:

My goal is to generate a list of symbolic parameters that other
functions in a package can Map[] over. For sake of example, suppose I
define the following 'utility' function as part of a larger package.

In[1]:= ClearAll["Global`*"]
In[2]:= shares[n_?IntegerQ/;n>0,s_Symbol:
s]:=Module[{i},Table[Symbol[ToString[s]<>ToString[i]],{i,n}]]
In[3]:= shares[2]

Out[3]= {s1,s2}

I would now like to include the attribute Constant to each of the
s1, ..., sn generated. What is the best way to do this?
My gut tells me that ideally I'd want to do this inside the shares[]
function itself, but I couldn't figure out how. The workaround I've
been toying with is to define another utility function:

In[4]:= setConstants[vars_]:=SetAttributes[#,Constant]&@vars

This seems to work ok...But does anyone see potential pitfalls with
this approach?

In[5]:= setConstants[shares[2]]
In[6]:= Attributes[s1]
In[7]:= Attributes[s2]

Out[6]= {Constant}
Out[7]= {Constant}

-RG


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