Paddy Mullen
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Paddy Mullen
@paddymullen.bsky.social
89 followers 550 following 120 posts
Boston/Newport. Python/PyData/Jupyter dev. Building the Buckaroo widgetto enhance the DataFrame viewing experience in Jupyter https://github.com/paddymul/buckaroo
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There is some good stuff on facebook. Fun post from the mainframers group about an IBM Sytem 370 card for the IBM PS/2. www.facebook.com/share/p/17tx...
Some people may ask, "What is a mainframe?". Well, the answer varies, everything from the multi-ton beasts, to the smaller versions. How small? May I present one of the mainframes I used to operate/administer, an IBM P/370. That's a complete IBM S/370 processor, including a full 16M of memory, on a single MCA card, which fit into a PS/2 model 95 system, and which ran VM/SP 5. Once, just for grins and giggles, I IPLed a second level VM system. Then, for more grins and giggles, I IPLed a third level VM system. But, it drove me crazy trying to remember which prompt to use for which system. Still, it demonstrated how thorough of an architecture implementation the card was. https://en.wikipedia.org/.../PC-based_IBM_mainframe... It was great having my own personal mainframe, which I used for product development and testing. It allowed me to do test installs of software on a real mainframe. Anyway, since some of y'all are posting really great pictures of machine rooms and big mainframes, I thought I'd offer a glimpse of what may be one of the smallest mainframes. 🙂 Oh, yeah, there was a follow-on product, the P/390, which was a S/390 system on a card. I lusted after one for many years, but was never able to justify it. And, there were a couple of proceeding products, the 7437, which was a full S/370 in a box about the size of a PS/2 model 95. There was also the XT/370, which was a PC/XT, with a card-set in it which was a partial implementation of the S/370 instruction set (one of which I happen to personally own). I was the team leader for the 7437 project and designed most of the CPU. It used an IBM bit slice (similar to the AMD 2900), and an IBM chip called FLAINE which implemented the floating point instructions. The rest of the CPU was built using mostly 7400F and 7400LS chips. The CPU had a writeable control store of 8K words of 96 bits each. Initially, we implemented dynamic address translation in 7400 logic, but then one of our engineers, Tak Ng, designed a CMOS chip to do the translation, and that went into the product-level release. The chip replaced a whole card worth of 7400 logic. The 7437 consisted of 6 cards, each approximately 9x12". The cards were the Instruction Unit, Execution Unit, Control Store, PS2 Interface and two 8 MB memory cards. Below is a photo of the writeable control store card. It's the only piece of hardware I still have. The XT/370 was based on a Motorola 68000 that IBM paid Motorola to modify to execute 370 instructions. The chip only could run CMS and not CP as it did not support supervisor state. Instead CP functions were provided by X86 code running on the PC. The P/370 and the P/390 chips were also designed by Tak Ng. The 7437, P/370 and P/390 were all done in Bill Beausoleil's IBM Fellow department by a team of 6 to 10 engineers and programmers. Bill wanted IBM to sell the 7437 for about $5,000. But that would have seriously broken IBM's pricing model vs the cost/performance of traditional mainframes like the 4341 which sold for something like $100,000. VM wanted to charge something like $100K for a 7437 license, Upper level executives were frightened that customers would buy a slew of 7437s instead of a 3090, costing IBM millions in profit. They swore that they would never let the 7437 go out the door if it meant losing the sale of even one 3090. In the end, they severely restricted who could buy a 7437 by bundling it with a 5080 graphics workstation and pricing it at $50,000.
June 17, 2025 at 12:59 PM
It works to arbitrary levels of nesting too
Buckaroo rendering a dataframes with a 3 level column MultiIndex
June 8, 2025 at 4:07 PM
And I now have pandas MultiIndex columns rendering nested locally.
Image showing buckaroo in marimo rendering a dataframe with multi index columns. the headers are nested
June 8, 2025 at 4:04 PM
I'm kneedeep in adding proper multi index-column support to Buckaroo. MultiIndexes are kind of a corner case of pandas, super powerful but often forgotten. Many tables don't display them properly because they are tricky. They don't serialize to JSON natively. #python #pandas #datascience #pydata
Mockup of multi indexes in storybook for buckaroo. This shows the nested column headers
June 7, 2025 at 4:27 PM
So, apparently SRAM NX 1x12 isn't a good fit on a 20 inch wheel. The RD hits the tire in the 3rd largest gear. #cargobike #bike
Image showing limited clearance between the derailleur and tire. Here the derailleur is in the 3rd or 4th largest gear Clearance between the derailleur and the ground when the derailleur is at it's most downward extended position. Riding the cargo bike on grass. Note the 20 inch rear wheel and 26 inch front wheel. A coastal scene is in the background.
June 5, 2025 at 5:09 PM
#Cargobike wheel build complete. Excited to try this tomorrow
May 17, 2025 at 12:54 AM
Autocleaning for buckaroo is really shaping up. This is the JLisp code editor showing operations that were added by an auto-cleaning strategy in purple. Multiple strategies are available and they can be cycled through quickly to try different approaches. #buildinpublic
May 1, 2025 at 3:59 PM
I have been working on a dataframe diffing tool built on top of buckaroo and datacompy. Here is a preview. Source here github.com/paddymul/buc...
January 18, 2025 at 5:47 PM
I found this Apollo book from the 70s wit what looks like computer generated charts. I'm curious what charting software existed back then. #dataviz
November 20, 2024 at 6:16 PM
I have to update the error messaging, because the next release will add backwards compatability with notebook 6.5.4 thanks to anywidget.
November 19, 2024 at 9:30 PM
Announcing buckaroo - the data wrangling tool for pandas. Manipulate dataframes with a GUI in jupyter, and generate python code. https://github.com/paddymul/buckaroo
May 11, 2023 at 6:08 PM