I have a problem with one code and hope that you can help me with that.
I have a list which looks like the following
List = {a, b, c, d, e}
the desired result is a new list with
{a, a*b, a*b*c, a*b*c*d, a*b*c*d*e}
Thanks in advance
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Accumulate takes the sum of the terms: this can be changed to the product of by changing the Plus to Times:
list = {a, b, c, d, e};
Accumulate@list /. Plus -> Times
{a, a b, a b c, a b c d, a b c d e}
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Block[{Plus = Times}, Accumulate@list]if you don't want to use replacements. $\endgroup$ – NonDairyNeutrino Feb 1 '20 at 5:58
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Another way:
list = {a, b, c, d, e};
E^Accumulate[Log[list]]
Since Accumulate equals Rest[FoldList[Plus,0,list]] , So Foldlist also works.
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Here's an operator version of @JM's suggestion in the comments:
list = {a, b, c, d, e};
FoldList[Times] @ list
{a, a b, a b c, a b c d, a b c d e}
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Another:
ReplaceList[{a, b, c, d,e}, { x__,___} :> Times@x ]
{a, a b, a b c, a b c d, a b c d e}
Comparing:
ReplaceList[{a, b, c, d,e}, { x__,___} :> Times@x ] == FoldList[Times] @ {a, b, c, d,e}
True
Fold[Times, 1, list]? AlsoListis a built-in symbol, so don't use it as a variable. Stick to variables starting with lower-case letters. $\endgroup$ – J. M.'s ennui♦ Jan 31 '20 at 16:11FoldList[]and notFold[]; thanks @Darth! $\endgroup$ – J. M.'s ennui♦ Jan 31 '20 at 16:17FoldList[Times, {a, b, c, d,e}]$\endgroup$ – A little mouse on the pampas Feb 1 '20 at 5:25