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Re: Re: Re: ListCurvePathPlot

  • To: mathgroup at smc.vnet.net
  • Subject: [mg96015] Re: [mg95995] Re: [mg95935] Re: [mg95909] ListCurvePathPlot
  • From: peter <plindsay.0 at gmail.com>
  • Date: Sun, 1 Feb 2009 04:41:39 -0500 (EST)
  • References: <200901291058.FAA18253@smc.vnet.net>

doesn't this just underline the impression that Wolfram are dropping
the ball on documentation ?  Doesn't matter how clever the programmers
or the users are - unless the product is authoritatively documented,
it is incomplete.

Peter

2009/1/31 DrMajorBob <btreat1 at austin.rr.com>:
> Interesting? Yes.
>
> Useful? I don't see how!
>
> Bobby
>
> On Fri, 30 Jan 2009 04:44:00 -0600, Curtis Osterhoudt <cfo at lanl.gov> wrote:
>
>> The following is rather interesting. I think it (with some imagination)
>> conforms to the definition given in the Mathematica Documentation, but
>> it wasn't what I was expecting.
>>
>> data = Table[RandomReal[{-1.3, 1.2}]*{Cos[t], Sin[t]},
>>        {t, 0, 6*Pi - 2*(Pi/6), Pi/6.1}];
>>
>>
>> {{0.25002688366379333, 0.}, {0.9356799430343185,
>>   0.5295589611737038},
>>    {0.10118796319464748, 0.16851424646497157},
>>    {-0.029188553024956546, -1.1332520553860652},
>>    {-0.23082153680912088, 0.4335135296822279},
>>    {0.7576710364167465, -0.48192811086842924},
>>    {0.9705776190593385, -0.05003046313427862},
>>    {1.0962492703177467, 0.5479411095599908},
>>    {0.6370536297044893, 0.9468064433345135}, {0.03136422751102095,
>>      0.4051894691695028}, {0.364963285556999, -0.7797519520786809},
>>    {-0.9341065689324766, 0.6640763628660812},
>>    {0.013137997466309304, -0.0013580598861936942},
>>    {-0.6906567258137415, -0.301834640354331},
>>    {0.566523954686374, 0.7549438704279434}, {0.07549928355009236,
>>      0.5831410479690148}, {0.4000794379862568, -0.9837423213746447},
>>    {0.24638452631107208, -0.19500664556832673},
>>    {1.1421844045687481, -0.17789046644213574},
>>    {0.11779527337621096, 0.04440716210668134},
>>    {-0.10502847445807519, -0.12589786231771516},
>>    {0.20288991501930384, 1.1133525098565278},
>>    {0.19075826931350767, -0.54838931166244}, {-0.013717694614866967,
>>      0.012056157937833439}, {0.8381916063026793, \
>> -0.17515740827734855},
>>    {-0.7711479671903417, -0.24617764515949736},
>>    {0.5886009181985181, 0.6359230898649515}, {-0.2787870392560766,
>>      -1.1813146432588384}, {-0.04025184234997148, 0.1382818883263678},
>>    {0.29420624689007885, -0.2867261088679789},
>>    {0.6823920131526263, -0.17971101963053693},
>>    {1.1400162086445282, 0.3002284190055794}, {-0.13739394197848387,
>>      -0.13390072706458242}, {0.00505513032785771,
>>   0.017366483784624985},
>>    {0.10886543986338092, -0.4612995589701644}}
>>
>> ListCurvePathPlot[data, Axes -> False]
>>
>>                      --C.O.
>>
>>
>>
>>
>>
>> On Thursday 29 January 2009 03:58:55 David Park wrote:
>>> I don't understand the new ListCurvePathPlot, which the Help page says:
>>> "attempts to reconstruct smooth curves defined by the specified set of
>>> points."
>>>
>>>
>>>
>>> This plot routine also has the option: InterpolationOrder. And the word
>>> "Curve" appears not only in the name but repeatedly in the descriptions.
>>> But look at the following example:
>>>
>>>
>>>
>>> data = Table[
>>>
>>>    RandomReal[{.8, 1.2}] {Cos[t], Sin[t]}, {t, 0, 2 \[Pi] - 2 \[Pi]/6,
>>>
>>>      2 \[Pi]/6}];
>>>
>>> ListCurvePathPlot[data,
>>>
>>>  InterpolationOrder -> 3,
>>>
>>>  Axes -> False]
>>>
>>>
>>>
>>> I don't see anything "smooth" or "curvy" about the results!  So it seems
>>> that these terms are a misdirection in understanding the use of the
>>> routine.
>>> It appears that what the routine actually does is reorder the points to
>>> give
>>> some simpler line (not curve) than the original set of points. But what
>>> is
>>> the criterion for this? Is this some well know computational geometry
>>> algorithm? Was InterpolationOrder included as an option by mistake? Did
>>> the
>>> implementation change from the original intention? What is the purpose
>>> of
>>> the routine? What is the relation of this and the spline functions?
>>>
>>>
>>>
>>> David Park
>>>
>>> djmpark at comcast.net
>>>
>>>  <http://home.comcast.net/~djmpark> http://home.comcast.net/~djmpark/
>>>
>>>
>>
>>
>>
>
>
>
> --
> DrMajorBob at longhorns.com
>
>


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