accumulate(Function,VisibleList) -- apply binary operator repeatedly

accumulate(Function,VisibleList) -- apply binary operator repeatedly

Synopsis:

Function: accumulate -- apply binary operator repeatedly

Input:

an instance of class Function.

an instance of class VisibleList.

Output:

an instance of class VisibleList.

accumulate(f,{x0,x1,...,xn}) -- computes the list {f(x0,x1),f(f(x0,x1),x2),...}.

i1 : accumulate(identity, {a,b,c,d,e})



o1 = {(a, b), ((a, b), c), (((a, b), c), d), ((((a, b), c), d), e)}



o1 : List

i2 : accumulate(plus, 0 .. 10)



o2 = (1, 3, 6, 10, 15, 21, 28, 36, 45, 55)



o2 : Sequence

Code:

     -- ../../../Macaulay2/m2/fold.m2:6-8
     accumulate(Function,VisibleList) := VisibleList => (f,v) -> (
          if #v === 0 then error "expected a nonempty list";
          accumulate(f,v#0,drop(v,1)))