PDL: Episode VI - a New Book

The title is clickbait. I ran short of time this week and am ~~recycling~~^Wconsolidating comments, replies and thoughts. Let's talk about Books!

I would love a new PDL Book. One that's completely different from the original to maximize the surface of engagement to a new audience. As a "sequel", It would have the advantage of being able to refer the reader to the first book for longer explanations and be able to jump right into how to solve significant problems. brian d foy has just finished his Mojolicious book, so I bet he's got loads of free time on his hands. (although I remember him in the middle of writing it in 2018, so you may have to wait a bit)

The premise behind the PDL Book is that it takes you on a tour of the features, trying to expose the useful parts as quickly as possible and yet still give you the Full Monty. In today's world, many coders, including yours truly, are unwilling adherents of SOOP (Stack Overflow Oriented Programming) with the attention span of 5-year olds who want to dive into the middle of a book and work their way backwards trying to understand the solution. I think it's an issue of motivation and, honestly, I'm surprised you've read this far before going off and checking your phone. :)

Never the less, people are still continuing to develop the first book. I think that the chapter on Installing PDL is vital to overcoming the barrier to entry. It has always been a sticking point and is off-putting if an installation doesn't work first time.

One of my favourite books for it's format is the Bad Data Handbook, 18 chapters of stories full of obstacles encountered, cursed at and eventually overcome. It makes you realize that Wisdom is not granted from on high, but hard-won by those who bear the burden of knowledge. I like to hear as much about what went wrong, both as a cautionary tale and as a ripping yarn. It keeps my attention to the end.

Taking as my motto, be the trouble you want to see in the world, these posts will be my contribution to a new PDL Book. With enough posts to make a couple of chapters, we could fire up a repo where those willing to write, edit, comment or code shall give this project the attention that it deserves. Not that it necessarily should be only PDL. Joe Kline's panel discussion in 2014 debated the question of whether Perl was a suitable language for science and one of the conclusions was as important to include talks about what things people were doing with Perl as it was to talk about how to do it. It helps to inform developers on which directions to consider with their code.

After some thought, I am also starting to get behind the idea of a "cookbook" format for Science with Perl. This might be a question for Dave Cross to weigh in on, as he's offered some assistance on the publishing process

Zubenel - if you can find the time to write about the trials and tribulations of getting PDL to install and run under Windows, successful or not, I would see that as a chapter in itself. There are so many niggles to work through in an ever-changing landscape. Did you manage to get it to install with Prima for displaying graphics?

Re-reading this post before submitting, I'm getting a warm glow from referring to the current PDL Book as the first book. It feels right.

Does anybody have a particular itch that you'd like to scratch with PDL and haven't had the time just yet?


Indeed! I have PDL installed on a Raspberry Pi, which is connected to a telescope. The camera returns a fits file. I'd love to be able to do a quick preview of the image.

I think, to make it more viewable, it'll need a little light correction. A histogram, some math, save as jpg.

There is a lot there I dont know how to do yet. I will keep the original fits file, I'd just like to make a little on screen preview

I also plan to capture many-many long exposure's. It would be neat to stack them for the preview as well.

tldr: histogram, light correct (probably not even the right term), stack fits files, create jpg preview for web page

Enkidu, as I am only Perl beginner I do not think that my trials will be very useful and could make an entire chapter. Nevertheless I might try to find time to write about it but I do not know where to post it. Maybe I could send it to you? Regarding the book it seems a good idea. IMO it could have chapters with different strategies how to deal with data as: how to import it, clean and transform it, run exploratory analysis, visualize, create regression models and interpret them.

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About Enkidu

user-pic I am a Freelance Scientist** and Perl is my Igor.