Re: List element manipulation
- To: mathgroup at smc.vnet.net
- Subject: [mg25464] Re: [mg25408] List element manipulation
- From: Tomas Garza <tgarza01 at prodigy.net.mx>
- Date: Sun, 1 Oct 2000 02:44:48 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
In[1]:=
{Drop[Range[116, 166, 8], -1], Last[Range[116, 166, 8]] - 1} // Flatten
Out[1]=
{116, 124, 132, 140, 148, 156, 163}
Tomas Garza
Mexico City
"Martin Rommel" <Martin_Rommel at mac.com> wrote:
> I want to decrement the last number in list. This ought to be easy,
but my
> initial attempts did not bear fruits:
>
> In[40]:=
> MapAt[Decrement, Range[116, 166, 8], -1]
>
> Decrement::"rvalue": "164 is not a variable with a value, so its
value
> cannot be changed."
>
> Out[40]=
> {116, 124, 132, 140, 148, 156, 164--}
>
> Do I need to use ReplacePart? That works but still gives me an error!
>
> In[53]:=
> Range[116, 166, 8] // ReplacePart[#, --Last[#], -1] &
>
> Set::"write": "Tag Last in Last[{116, 124, 132, 140, 148, 156,
164}] is
> Protected."
>
> Out[53]=
> {116, 124, 132, 140, 148, 156, 163}
>
> Different error here:
>
> In[51]:=
> Range[116, 166, 8] // ReplacePart[#, --#[[-1]], -1] &
>
> Set::"setps": "{116, 124, 132, 140, 148, 156, 164} in assignment
of part
> is not a symbol."
>
> Out[51]=
> {116, 124, 132, 140, 148, 156, 163}
>
>
> Anybody out there able to enlighten me?