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Philosophical Scaling Question [message #51605] Mon, 04 December 2006 08:15 Go to next message
David Fanning is currently offline  David Fanning
Messages: 11724
Registered: August 2001
Senior Member
Folks,

With no answers to my weekend questions about logarithmic
color bars I'm flying blind this morning. And I seem to be
running into theoretical difficulties. Can anyone help?

Suppose I had a color table (color table 33 comes to mind)
where each color vector had a min of 0 and a max 0f 255.

IDL> Loadct, 33, /Silent
IDL> TVLCT, r, g, b, /Get
IDL> MinMax, r
0 255
IDL> MinMax, g
0 255
IDL> MinMax, b
0 255

And suppose I also have an image that is scaled in
the same way:

IDL> image = Loaddata(7)
IDL> MinMax, image
0 255

And finally, suppose I have a way to scale such data
sets in a logametric way, say a function LOGSCL.

IDL> .compile LOGSCL
Compiled module: LOGSCL.

My hypothesis is that there are two ways to display this
data "logarithmically". I can leave the color table vectors
alone, and scale the image data. Or, I can leave the image
alone and scale the color vectors. Either way should result
in exactly the same display.

The problem is, it doesn't. :-(

Window, XSize=400, YSize=350, 0
Loadct, 33, /Silent
TVImage, image

Window, XSize=400, YSize=350, 1
Loadct, 33, /Silent
TVImage, LogScl(image)

Window, XSize=400, YSize=350, 2
Loadct, 33, /Silent
TVLCT, r, g, b, /Get
TVLCT, LogScl(r), LogScl(g), LogScl(b)
TVImage, image

Does anyone have a good idea for why not?

Cheers,

David

P.S. And please don't tell me there is something wrong
with LOGSCL, as this is *not* the answer I want to
hear. :-(

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Re: Philosophical Scaling Question [message #51700 is a reply to message #51605] Tue, 05 December 2006 11:57 Go to previous messageGo to next message
David Fanning is currently offline  David Fanning
Messages: 11724
Registered: August 2001
Senior Member
R.G. Stockwell writes:

> Assuming you made the pdf, can you put an obvious message on
> each page, like "Paul van Delst's personal copy" as a giant
> watermark or something?
> At least then you would know who is handing out pdfs.

Coyote just notified me that he has worked out an arrangement
with the SportsByBrooks girls to assign a unique picture
element to each file so we can keep track of it. This
pretty much assures the PDF file will get read, I guess, but
it's a sorry marketing ploy, if you ask me. :-(

Cheers,

David

P.S. I guess this is who he has hired for the big
IEPA shindig we having going on this weekend:

http://www.sportsbybrooks.com/

What a disaster! I'll let you know how it goes.
(So far, Karsten Rodenacker is the only one to RSVP,
an he apparently couldn't get the Andechs beer through
security.)

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Re: Philosophical Scaling Question [message #51702 is a reply to message #51605] Tue, 05 December 2006 11:37 Go to previous messageGo to next message
news.qwest.net is currently offline  news.qwest.net
Messages: 137
Registered: September 2005
Senior Member
"David Fanning" <news@dfanning.com> wrote in message
news:MPG.1fdf3f691aece911989e1d@news.frii.com...
> Paul van Delst writes:
>
>> BTW, my copy of your original book was lost (i.e. "borrowed".. grrr)
>> years ago. Is that
>> available as a PDF?
>
> Yes, I have the book available in PDF format. And,
> on occasion, I will distribute it as such for people
> who understand that piracy is a big deal for people
> who depend on book sales to educate their children.

Assuming you made the pdf, can you put an obvious message on
each page, like "Paul van Delst's personal copy" as a giant
watermark or something?
At least then you would know who is handing out pdfs.
Re: Philosophical Scaling Question [message #51716 is a reply to message #51605] Tue, 05 December 2006 07:34 Go to previous messageGo to next message
David Fanning is currently offline  David Fanning
Messages: 11724
Registered: August 2001
Senior Member
Paul van Delst writes:

> BTW, my copy of your original book was lost (i.e. "borrowed".. grrr) years ago. Is that
> available as a PDF?

Yes, I have the book available in PDF format. And,
on occasion, I will distribute it as such for people
who understand that piracy is a big deal for people
who depend on book sales to educate their children.

It seems even a life of pro bono service to the community
isn't enough protection money to keep authors from being
ripped off. It's really sad. So, anyway, I try to be
very, very careful.

But I'm happy to replace your lost copy with a PDF version,
Paul. :-)

Cheers,

David
--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Re: Philosophical Scaling Question [message #51719 is a reply to message #51605] Tue, 05 December 2006 07:12 Go to previous messageGo to next message
Paul Van Delst[1] is currently offline  Paul Van Delst[1]
Messages: 1157
Registered: April 2002
Senior Member
David Fanning wrote:
> Brian Larsen writes:
>
>> When will we see this book, seems my grant could use sending some money
>> your way? Is it 3rd edition of IDL Programming Techniques or something
>> different.
>
> We'll probably never see it. :-(
>
> At the moment my thinking is that the 3rd Edition will weigh
> in at about 15 pounds if I put into it everything I want to
> put into it. I'm pretty sure no one will read the damn thing.
>
> So I've been thinking about a slimmer volume entitled
> "Interactive IDL: What You Can Still Do at a Command
> Line With the Dopey Old Direct Graphics". I'm going
> to bet a fair bit of money this will *still* sell like
> hotcakes. :-)

I agree with Braedley. I'm into tomes at the moment *provided* they come in both print and
pdf. The pdf's go on my various computers for immediate reference/searching and the tome
stays at home for reading during, uh, erm, quieter moments. I realise there's a piracy
issue involved, but I wish more publishers pulled their heads out of the sand and made pdf
e-books available (I hope someone from O'Reilly is reading this :o)

BTW, my copy of your original book was lost (i.e. "borrowed".. grrr) years ago. Is that
available as a PDF?

paulv

--
Paul van Delst Ride lots.
CIMSS @ NOAA/NCEP/EMC Eddy Merckx
Ph: (301)763-8000 x7748
Fax:(301)763-8545
Re: Philosophical Scaling Question [message #51735 is a reply to message #51605] Mon, 04 December 2006 11:21 Go to previous messageGo to next message
David Fanning is currently offline  David Fanning
Messages: 11724
Registered: August 2001
Senior Member
Braedley writes:

> Heh, I'd buy that 15 pound tome. This despite the fact that I still
> haven't read the last 5 chapters (7 months after the fact) of edition
> 1. Probably something I should have done before embarking on
> maintaining a beast of a widget program without much documentation, but
> what's done is done. Your book, website, and programs have saved me
> many headaches over the past several months.

Well, if your gratitude extends to the monetary, you
can always make a donation on the main page. Coyote
matches the gifts and they go to a local charity.
This month, a local safe house for battered women.

Cheers,

David

P.S. Coyote prefers a gift like this more than the
cases of beer he is promised, but never receives.
And, anyway, he has a hard time matching, and then
GIVING AWAY (!!) the beer donations. :-(

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Re: Philosophical Scaling Question [message #51736 is a reply to message #51605] Mon, 04 December 2006 11:13 Go to previous messageGo to next message
Braedley is currently offline  Braedley
Messages: 57
Registered: September 2006
Member
David Fanning wrote:
> Brian Larsen writes:
>
>> When will we see this book, seems my grant could use sending some money
>> your way? Is it 3rd edition of IDL Programming Techniques or something
>> different.
>
> We'll probably never see it. :-(
>
> At the moment my thinking is that the 3rd Edition will weigh
> in at about 15 pounds if I put into it everything I want to
> put into it. I'm pretty sure no one will read the damn thing.
>
> So I've been thinking about a slimmer volume entitled
> "Interactive IDL: What You Can Still Do at a Command
> Line With the Dopey Old Direct Graphics". I'm going
> to bet a fair bit of money this will *still* sell like
> hotcakes. :-)
>
> Cheers,
>
> David
>
> --
> David Fanning, Ph.D.
> Fanning Software Consulting, Inc.
> Coyote's Guide to IDL Programming: http://www.dfanning.com/
> Sepore ma de ni thui. ("Perhaps thou speakest truth.")

Heh, I'd buy that 15 pound tome. This despite the fact that I still
haven't read the last 5 chapters (7 months after the fact) of edition
1. Probably something I should have done before embarking on
maintaining a beast of a widget program without much documentation, but
what's done is done. Your book, website, and programs have saved me
many headaches over the past several months.

Braedley
Re: Philosophical Scaling Question [message #51738 is a reply to message #51605] Mon, 04 December 2006 10:45 Go to previous messageGo to next message
David Fanning is currently offline  David Fanning
Messages: 11724
Registered: August 2001
Senior Member
Brian Larsen writes:

> When will we see this book, seems my grant could use sending some money
> your way? Is it 3rd edition of IDL Programming Techniques or something
> different.

We'll probably never see it. :-(

At the moment my thinking is that the 3rd Edition will weigh
in at about 15 pounds if I put into it everything I want to
put into it. I'm pretty sure no one will read the damn thing.

So I've been thinking about a slimmer volume entitled
"Interactive IDL: What You Can Still Do at a Command
Line With the Dopey Old Direct Graphics". I'm going
to bet a fair bit of money this will *still* sell like
hotcakes. :-)

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")
Re: Philosophical Scaling Question [message #51740 is a reply to message #51605] Mon, 04 December 2006 10:30 Go to previous messageGo to next message
Brian Larsen is currently offline  Brian Larsen
Messages: 270
Registered: June 2006
Senior Member
> I'll put you on the list of people who want to buy the new book. :-)

When will we see this book, seems my grant could use sending some money
your way? Is it 3rd edition of IDL Programming Techniques or something
different.

But yes count me in either way.

Brian
Re: Philosophical Scaling Question [message #51790 is a reply to message #51702] Tue, 05 December 2006 13:49 Go to previous message
Paul Van Delst[1] is currently offline  Paul Van Delst[1]
Messages: 1157
Registered: April 2002
Senior Member
R.G. Stockwell wrote:
> "David Fanning" <news@dfanning.com> wrote in message
> news:MPG.1fdf3f691aece911989e1d@news.frii.com...
>> Paul van Delst writes:
>>
>>> BTW, my copy of your original book was lost (i.e. "borrowed".. grrr)
>>> years ago. Is that
>>> available as a PDF?
>> Yes, I have the book available in PDF format. And,
>> on occasion, I will distribute it as such for people
>> who understand that piracy is a big deal for people
>> who depend on book sales to educate their children.
>
> Assuming you made the pdf, can you put an obvious message on
> each page, like "Paul van Delst's personal copy" as a giant
> watermark or something?
> At least then you would know who is handing out pdfs.

(Weird - I'm getting the news posts all out of order...)

Isn't that the defacto norm for the more reasonable e-book providers? [*] The pdf's I have
that aren't open source display a "specially prepared for Paul van Delst" at the bottom of
each page (along with other info).

The one O'Reilly pdf I have is the *only* copyrighted work in my e-library not to have any
apparent security. Bizarre.

Anyway....

paulv

[*] See
http://www.pragmaticprogrammer.com/
and
http://www.manning.com/
--
Paul van Delst Ride lots.
CIMSS @ NOAA/NCEP/EMC Eddy Merckx
Ph: (301)763-8000 x7748
Fax:(301)763-8545
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