[calc] what happened to a i ???

[calc] what happened to a i ???

[boffi]

If I try to integrate sin(x) sin(2 x) this is what I get NOW, using
Emacs 25 on Debian and the calc version (?) that is distributed with it

 | --- Emacs Calculator Mode ---
 |       /
 |      | 
 | 1:   | sin(x) sin(2 x) dx
 |      | 
 |     /  
 | 
 |     .
 |

while I'm pretty sure that I've been able to use calc to integrate such
simple expression at some point in the past.

On the other hand, I've installed a very old version of XEmacs and the
corresponding old version of calc and I have

 | --- Emacs Calculator Mode ---
 | 2:  sin(x) sin(2 x)
 | 
 |     2       3
 | 1:  - sin(x)
 |     3
 | 
 |     .
 |

so I'm inclined to think that I've something done something wrong...

Do I have to set some variable to get back the old behavior of calc?

Thank you in advance,
                                                                g

Re: [calc] what happened to a i ???

[boffi]

boffi <giacomo.boffi@gmail.com> writes:

> Do I have to set some variable to get back the old behavior of calc?

I have found that calc has a *Trace* buffer mechanism...

old XEmacs, old calc

 |  1  Integrating sin(X) sin(2 X)...
 |  1  Found 2:3 sin(X)^3 => 2:3 sin(X)^3
 |  1  Integral of sin(X) sin(2 X)  is  2:3 sin(X)^3
 | 
 | 
 | Begin rewriting
 |                                  2:3 sin(X)^3
 | 
 | (Phase 1)
 | 
 | Done rewriting:
 |                                  2:3 sin(X)^3

Emacs 25, its calc

 |  1  Integrating sin(X) sin(2 X)...
 |  1  Found cancelled => cancelled
 |  1  Simplifying... no change
 |   1 Integrating by substitution, u = 2 X
 |   2 Integrating sin(X / 2) sin(X) / 2...
 |   2 Found cancelled => cancelled
 |   2 Simplifying... simplified
 |   3 Integrating sin(X) sin(X / 2) / 2...
 |   3 Found cancelled => cancelled
 |   4 Integrating sin(X) sin(X / 2)...
 |   4 Found cancelled => cancelled
 |   4 Integral of sin(X) sin(X / 2)  is  nil
 |   3 Integral of sin(X) sin(X / 2) / 2  is  nil
 |   2 Integral of sin(X / 2) sin(X) / 2  is  nil
 |   2 Integrating 1:2 sin(X / 2) sin(X)...
 |   2 Found cancelled => cancelled
 |   2 Simplifying... simplified
 |   3 Integrating sin(X) sin(X / 2) / 2...
 |   3 Found cancelled => cancelled
 |   4 Integrating sin(X) sin(X / 2)...
 |   4 Found cancelled => cancelled
 |   4 Integral of sin(X) sin(X / 2)  is  nil
 |   3 Integral of sin(X) sin(X / 2) / 2  is  nil
 |   2 Integral of 1:2 sin(X / 2) sin(X)  is  nil
 |   1 Integrating by substitution, u = sin(X)

it seems that the old calc has more canned results under its belt,
but of course I may be wrong...

yours
                                                      g