List element manipulation
- To: mathgroup at smc.vnet.net
- Subject: [mg25408] List element manipulation
- From: "Martin Rommel" <Martin_Rommel at mac.com>
- Date: Fri, 29 Sep 2000 01:06:58 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
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?
Thanks, Martin