Re: pick out an element from list

*To*: mathgroup at smc.vnet.net*Subject*: [mg98082] Re: pick out an element from list*From*: Ray Koopman <koopman at sfu.ca>*Date*: Sun, 29 Mar 2009 02:48:46 -0500 (EST)*References*: <gqkup8$458$1@smc.vnet.net>

On Mar 28, 3:39 am, bahadir <bahadirgurbu... at hotmail.com> wrote: > i have a list with n element.i want to pick out an element from the list,= and to deduct the element from all the other residual elements. This proce= ss is the first step. i must apply all elements of the list, invariably. Na= mely, in conclusion, i will obtain n list with n-1 elements. now, i will tr= y to explain as numerically. let element number of the list be 2500. and i = am picking out the first element of the list. and i'm deducting the first e= lement from the residual elements of the list. and now, i have a list with = 2499 elements.after that, i'm passing the second element, and i'm applying = the same processes. =C4=B1 can't do this, can anyone help me??? The process simplifies. If the intial list is {a, b, c, d} then the first step gives {a, b-a, c-a, d-a}. The second step gives {a, b-a, (c-a)-(b-a), (d-a)-(b-a)} = {a, b-a, c-b, d-b}. Finally, the third step gives {a, b-a, c-b, (d-b)-(c-b)} = {a, b-a, c-b, d-c}. In[1]:= (#-Join[{0},Most@#]&) @ {a,b,c,d,e,f} Out[1]= {a, -a+b, -b+c, -c+d, -d+e, -e+f}