Re: Mathematica 6.0 easier for me ... (small review)
- To: mathgroup at smc.vnet.net
- Subject: [mg76585] Re: Mathematica 6.0 easier for me ... (small review)
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Thu, 24 May 2007 06:08:55 -0400 (EDT)
- Organization: Uni Leipzig
- References: <f30vpv$mkn$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
Hi,
lis = {{1, 10}, {2, 10}, {9, 10}, {11, 20}, {12, 20}, {19, 20}, {11,
30}, {12, 30}, {13, 30}};
Partition[lis, 2, 1] /. {{_, a_}, {_, a_}} :> Sequence[]
should return a list of all pairs where the second enty change.
Regards
Jens
Paul at desinc.com wrote:
> This is far from an in depth review. I have been working on a fun
> problem and have had difficulty making progress with 5.2. Something
> about 6.0 made it easier and I finally solved it. I think it is the
> following:
>
> 1. Mathematica 6.0 is higher speed/lower drag. I find myself using
> things I used to groan about looking up for the millionth time. I
> think Wolfram really listened to all the little gripes. I believe the
> liberty of the "obvious use" is indespensable. Never having to look
> up Display again to suppress output!!! The language is becoming much
> more consistent. ";" suppresses output!
>
> 2. In addition, I like the new google style help. I wish it would
> default to typing so I didn't have to delete what was there. Or at
> least highlight it.
>
> 3. What wasn't there is finally there. The graphics commands are
> MUCH, MUCH better. Rotatable graphics that stay rotated when rendering
> again is awesome. I'm also addicted to Manipulate[]. Most
> incredible.
>
> 4. At work, I haven't had to resort to other programs because
> Mathematica wasn't the best choice. This is extremely nice. BTW,
> There's a "temporal" advantage with procedural programming that hasn't
> been apparant to me in functional or rule. Still working on it. Maybe
> someone can help. If I have
> lis={{1,10},{2,10},...{9,10},{11,20},{12,20}...{19,20}
>
> How do I use functional and/or rule to determine where the second
> number (lis[[i,2]]) jumped from 10 to 20 to 30 and save the pair.
> Assuming there was noise, I only want to store the first 10->20, then
> look for 20->30 and so on. So in time, I want my search to change as
> I progress through the list. Any input appreciated!
>
> 5. What is there, is better. ListPlot is one example. I am using
> colors features that were less accessible to me in 5.2.
>
> 6. Very few gotchas. I have only found one, though it keeps biting
> me. If I have two lists, one from 0-100 in both axis and the other
> from 0-1000 in both axis, Show[] will truncate!
>
> lisA = Table[i^2, {i, 0, 1000}];
> lisB = Table[i, {i, 0, 100}];
> p1 = ListPlot[lisA, Joined -> True];
> p2 = ListPlot[lisB, Joined -> True];
> Show[p1, p2]
> Show[p2, p1]
>
> The first plot parameter to Show[] determines truncation. 5.2 did not
> do this!! Of course, change Joined to PlotJoined for 5.2. A small
> gotcha, but never the less a gotcha that burned me once already. My
> fault. New is not worse, just different. To me, Show[] simply
> Showed. Now it is not. PlotRange->All fixes this. I wish there was
> a way to default to All for Show[].
>
> One small, small inconsitency is BaseX number handling. BaseForm
> outputs some pretty to the eye format, but is harder to work with. I
> would add:
>
> ToBase[{"String",NumberBaseFrom},
> NumberBaseTo,
> Pad digits (optional)]
> ToBase[{Number,10},
> NumberBaseTo,
> Pad digits (optional)]
>
> Output rules would be {"String",BaseNumber} when NaseNumber was not
> equal to 10. Or {Number,10}. If someone wants to use this, they will
> need to know lists. This is a highly re-usable skill. To convert a
> list of binary strings is somewhat sumbersome.
>
> lis = {"1111", "0100"};
> Map[ ToExpression["2^^" <> #] &, lis]
>
> Not exactly intuitive based on other experiences with Mathematica.
> Still do able. I guess the other way, the user must create:
> lis = {{"1111",2}, {"0100",2}};
>
> Maybe
> ToBase[String,
> NumberBaseFrom,
> NumberBaseTo,
> Pad digits (optional)]
> ToBase[Number,
> 10, (*Implicit, but still stated for consistency *)
> NumberBaseTo,
> Pad digits (optional)]
>
> ToBase["1111", 2, 10]
> 15
>
> ToBase[15, 10, 2, 8]
> "00001111"
>
> The user would have to keep track of what base the string was in. This
> is probably a lot easier than anything else.
>
> I go through this to indicate I have trouble thinking of anything
> defintively better. I don't envy Wolfram's task in continually
> improving Mathematica. I appreciate the results.
>
>
>
> Nice job to Wolfram. Can't wait to see 6.1 :)
>
> Best Regards,
> Paul
>