How to substitute inside Hold? How to create table of summation (with Sigma symbol) expressions?

Asked Jan 04 '15 at 17:50

Active Jan 04 '15 at 17:50

Viewed 157 times

I would like to create table of summation expressions, which are not evaluated, but summation limits are substituted.

I can't accomplish this so far.

If I write

enter image description here

I get summation expanded.

If I write:

enter image description here

I get "Hold" word displayed and summation limits not substituted.

If I write:

enter image description here

I get limits not substituted.

asked Jan 04 '15 at 17:50

Suzan Cioc

3

You have been a member for 2 years and 11 months and you post images instead of actual code ? – Sektor Jan 04 '15 at 18:01
Because visual representation matters here. The code is not very smart anyway. – Suzan Cioc Jan 04 '15 at 18:10
3

Providing code would be a good idea nevertheless. – Yves Klett Jan 04 '15 at 18:21
1

Use With[{n=n},... to inject into held expressions. – Kuba Jan 04 '15 at 19:20
Closely related: 7756 but I'd even say a duplicate. – Kuba Jan 04 '15 at 19:23
Inactive may be of interest here: Table[Inactive[Sum][Subscript[a, i, j], {i, m}, {j, n}], {m, 3}, {n, 4}]. Otherwise: Table[HoldForm@Sum@## & @@ {Subscript[a, i, j], {i, m}, {j, n}}, {m, 3}, {n, 4}] – Mr.Wizard Jan 05 '15 at 10:44

0 Answers0