Re: expanding a list
- To: mathgroup at smc.vnet.net
- Subject: [mg42634] Re: expanding a list
- From: Bill Rowe <listuser at earthlink.net>
- Date: Fri, 18 Jul 2003 05:25:34 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
On 7/17/03 at 3:45 AM, Alan.Kelly at tcd.ie (Alan Kelly) wrote:
> I have two lists - both of the same length. The first contains a
> list of probabilities. For example, suppose the list length is 4
> (although in practice it would be much longer) and is of the
> following form:
> plist = {0.252, 0.252, 0.257, 0.235}.
> The second contains a list of integers:
> flist = {7,5,6,4}.
> I wish to take the first element of plist and replicate that value
> using the first element of flist. Similarly for the remaining
> elements.
> I should finish with a list of length 7+5+6+4 or 22.
Try
In[1]:=
plist={0.252,0.252,0.257,0.235};
flist={7,5,6,4};
Flatten@MapThread[Table[#1,{#2}]&,{plist,flist}]
Out[2]=
{0.252, 0.252, 0.252, 0.252, 0.252, 0.252, 0.252, 0.252,
0.252, 0.252, 0.252, 0.252, 0.257, 0.257, 0.257, 0.257,
0.257, 0.257, 0.235, 0.235, 0.235, 0.235}