Local variables whose definitions depend on each other [duplicate]

Question

Consider the following (pseudo-)function definition:

f[l_] := Let[{
          a = Length[l],
          b = First[l],
          c = b/a,
         }, c*10]

So for instance, f[{2,3,4,5}] should output 5.

Currently, I only know variants for Let that

What is the most simple way to define local variables whose definitions may depend on each other (upwards)?

RunnyKine · Accepted Answer · 2014-08-27 16:45:19Z

6

If you have Version 10 use the function Where in the GeneralUtilities package like this:

Needs["GeneralUtilities`"]

f[l_] := Where[a = Length[l], b = First[l], c = b/a, c*10]

Then:

f[{2, 3, 4, 5}]

5

answered Aug 27, 2014 at 16:45

RunnyKine

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Öskå · Accepted Answer · 2014-08-27 17:11:13Z

4

Why not just this?

f[l_] := Block[{a,b,c},
          a = Length[l];
          b = First[l];
          c = b/a;
          c*10]

Then

f[{2, 3, 4, 5}]

Öskå

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answered Aug 27, 2014 at 17:09

rhermans

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2 Answers 2