# Show Full Output button broken for all large outputs

I use Mathematica 9.0.1.0 on Mac OS X 10.10.3.

As an example of my issue, we can follow along with the example from the documentation page for $OutputSizeLimit. Quoting from that page: This produces output that is somewhat lengthy: In:= Expand[(x + 3 y)^27]  Out= x^27 + 81 x^26 y + 3159 x^25 y^2 + 78975 x^24 y^3 + 1421550 x^23 y^4 + 19617390 x^22 y^5 + 215791290 x^21 y^6 + 1942121610 x^20 y^7 + 14565912075 x^19 y^8 + 92250776475 x^18 y^9 + 498154192965 x^17 y^10 + 2309623985565 x^16 y^11 + 9238495942260 x^15 y^12 + 31979409030900 x^14 y^13 + 95938227092700 x^13 y^14 + 249439390441020 x^12 y^15 + 561238628492295 x^11 y^16 + 1089463220014455 x^10 y^17 + 1815772033357425 x^9 y^18 + 2580307626350025 x^8 y^19 + 3096369151620030 x^7 y^20 + 3096369151620030 x^6 y^21 + 2533392942234570 x^5 y^22 + 1652212788413850 x^4 y^23 + 826106394206925 x^3 y^24 + 297398301914493 x^2 y^25 + 68630377364883 x y^26 + 7625597484987 y^27 Set $OutputSizeLimit to be rather small:

In:= $OutputSizeLimit = 4000  Out= 4000 Now the same output as before is shown in a shortened form: In:= Expand[(x + 3 y)^27]  Out= A very large output was generated. Here is a sample of it. x^27 + 81 x^26 y + 3159 x^25 y^2 + 78975 x^24 y^3 + 1421550 x^23 y^4 + 19617390 x^22 y^5 + 215791290 x^21 y^6 + 1942121610 x^20 y^7 + <<13>> + 3096369151620030 x^6 y^21 + 2533392942234570 x^5 y^22 + 1652212788413850 x^4 y^23 + 826106394206925 x^3 y^24 + 297398301914493 x^2 y^25 + 68630377364883 x y^26 + 7625597484987 y^27  [Show Less] [Show More] [Show Full Output] [Set Size Limit…] So far so good. But when I click any of the "Show Less", "Show More", or "Show Full Output" buttons, I am faced with the following error message:$OutputSizeLimit::noout: This output cannot be updated because Out has no value.

This occurs for any "very large output" in any notebook. What is going wrong and how can I fix this?

• What evaluation of $HistoryLength returns for you? – Alexey Popkov Apr 12 '15 at 5:49 • Wow: You got it in one guess! Absolutely right, I had set $HistoryLength = 0 to help with memory consumption. – thecommexokid Apr 12 '15 at 5:59

The reason is that you have empty history because you set $HistoryLength = 0 (as you confirm in the comments). I recommend setting $HistoryLength to be at least 3 in order to get the [Show Full Output] button working in the most practical cases.