Re: List Help Needed

*To*: mathgroup at smc.vnet.net*Subject*: [mg68867] Re: List Help Needed*From*: albert <awnl at arcor.de>*Date*: Mon, 21 Aug 2006 06:33:23 -0400 (EDT)*References*: <ecbo4l$r5j$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Nimrod wrote: > What combination of Map, MapAt, ... > > will transform {{a,b},{c,d},...} to {{a,f[b]},{c,f[d]},...} > > Thanks in advance. > > Nimrod I think you will need a pure function that handles the first and second entry in the lists differently. This is a possibility with Map: In[6]:= Map[{#[[1]],f[#[[2]]]}&,{{a, b}, {c, d}}] Out[6]= {{a, f[b]}, {c, f[d]}} For this case, Apply results in somewhat shorter code: In[8]:= Apply[{#1,f[#2]}&,{{a, b}, {c, d}},{1}] Out[8]= {{a, f[b]}, {c, f[d]}} And using the short form of Apply[,{1}] it becomes even shorter: In[9]:= {#1,f[#2]}& @@@ {{a, b}, {c, d}} Out[9]= {{a, f[b]}, {c, f[d]}} hth, albert