Specify number of elements instead of step in Table

Question

I think I have seen what I was looking for a ong time ago but I can't see nothing such in documentation.

Quite often, I would like to create a Table with given bounds and number of elements, rather than calculating the appropriate step.

For example, instead of Table[f[i],{i,10,11,0.25}] I am looking for something like ...[f[i],{i,10,11,5}] where 5 corresponds to the number of elements.

Is there a built-in function/option for this?

possible duplicate http://mathematica.stackexchange.com/questions/6949/calling-table-with-custom-iterator?rq=1 — Sascha, Jan 07 '16 at 16:37
@Sascha That's exactly what I was looking for, thank you. Your answer with Array works, but it can be sometimes a bit more complicated to use, as I understand it. E.g.: Table[Map[Plus[#, 2] &, {i}], {i, 1, 5, .5}] becomes Array[Map[Plus[#, 2] &, {##}] &, 9, {1., 5}]. — anderstood, Jan 07 '16 at 16:49
try Array[{Plus[#, 2]}&, 9, {1., 5}]. You are right that Table and Array behave differently. I personally prefer the way Array works because you don't have to think about the structure you want to obtain rather you think about a function you want to apply for creating your list. — Sascha, Jan 07 '16 at 16:56

score 3 · Answer 1 · edited May 23 '17 at 12:35

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For anything rectangular you can use Array as in

Array[f, 5, {10., 11.}]

which yields

{f[10.],f[10.25],f[10.5],f[10.75],f[11.]}

Note: As discussed here on stack overflow Array is faster than Tablefor multidimensional lists.

edited May 23 '17 at 12:35

Community

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answered Jan 07 '16 at 16:24

Sascha

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score 2 · Accepted Answer · answered Jan 07 '16 at 16:47

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Beginning with V10.1,

Table[f[i // N], {i, Subdivide[10, 11, 4]}]

or

f /@ N[Subdivide[10, 11, 4]]

will work. Note that you must give 4 rather 5, because the last argument indicates the number of divisions not the number of elements.

answered Jan 07 '16 at 16:47

m_goldberg

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score 0 · Answer 3 · answered Jan 07 '16 at 16:34

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f /@ FindDivisions[{10, 11}, 4] // N

answered Jan 07 '16 at 16:34

eldo

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FindDivisions actually entails the mean pitfall that it chooses divisions it deems "nice" and does not necessarily do what you asked for (e.g. first and/or last entry slightly outside the defined scope). In my opinion the documentation for FindDivision should have a "Possible Issues" section – Sascha Jan 07 '16 at 17:04

Specify number of elements instead of step in Table

3 Answers3