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jmuhlich

Re:CDC File Transfer on Wednesday October 01, 2025 @11:14AM (#45438683)
Try this: https://alexsaveau.dev/blog/projects/performance/files/fuc/f...

> The key insight is that file operations in separate directories don’t (for the most part) interfere with each other, enabling parallel execution.

It really is magically fast.

EDIT: Sorry, that tool is only for local copies. I just remembered you're doing remote copies. Still worth keeping in mind.

CPython still needs to update reference counts after the fork even if your python code itself doesn't modify any data, making Copy on Write less helpful than it would first appear. Monolithic memory buffers like numpy arrays can be shared efficiently via CoW, but rich data structures with many PyObjects suffer from the refcounting issue.
Re:BioModels on Tuesday March 07, 2023 @12:35PM (#35058298)
The systems of differential equations produced by these types of models tend to be analytically intractable, so "numerical methods" are absolutely essential here. The phrase you want to look for is "initial value problem" (IVP): you know the initial values of the quantities described by the equations and you want to find out how those quantities evolve over time.

https://en.wikipedia.org/wiki/Numerical_methods_for_ordinary...

Re:Show HN: Clamshell- an experimental Python based shell on Saturday January 28, 2023 @01:29PM (#34560100)
I like pdbpp. Make sure to install from source as there hasn’t been a release in a while.

https://github.com/pdbpp/pdbpp

Re:Every modeler is supposed to be a great Python programmer on Thursday December 08, 2022 @10:13PM (#33916963)
To make this more clear as I have had the same experience and want more people to enjoy it: Mamba is more or less a drop-in replacement for the conda tool with the guts rewritten in C++ and as a result is much faster to resolve dependencies -- I want to say an order of magnitude faster or more. It's even noticeably faster at downloading and installing. You just

  conda install -c conda-forge mamba
in your base environment and then you can start running mamba instead of conda.
Re:QOIR: A fast, simple, lossless image file format on Wednesday December 07, 2022 @01:18AM (#33891236)
TIFF will support that size and larger. It can use JPEG or ZLIB compression as standard, or even WEBP or JPEG-XL which are unofficially supported by a small number of TIFF libraries.
I’ve used those Snappy brand cutters in a handheld cordless drill. It’s workable but tricky. You need to start with light pressure and high speed until the cutters score a clean circle, then gradually increase the pressure. The workpiece absolutely needs to be clamped down with zero movement, and it helps if you can find a way to brace your upper body and the drill as you work. The trickiest part is keeping the cutter perfectly square to the work in both axes —- if you tip it too far you’re likely to shatter the cutter as the metal is very brittle.
Re:There’s no such thing as a tree (phylogenetically) on Tuesday December 21, 2021 @11:03AM (#29638663)
That species of moth doesn’t exist on the American continent but other similar and related ones do, whose range does overlap with that of hummingbirds. For example:

https://en.m.wikipedia.org/wiki/Hemaris_thysbe

This post claims the history of which releases closed which holes is a bit more complicated and that 8u191 really is the first release to prevent this particular exploit. However it also points out that it’s still possible to achieve RCE via log4j template expansion in certain Tomcat and Websphere configurations:

https://mbechler.github.io/2021/12/10/PSA_Log4Shell_JNDI_Inj...

You might be interested in this 100% compatible SB 1.0 reimplementation (including 8051 of course) : https://github.com/schlae/snark-barker
Re:How to properly load a dishwasher (2020) on Wednesday September 08, 2021 @08:27PM (#28464734)
Also if the upper tray is height-adjustable, check the rubber one-way valve flaps in the middle of the supply tube that runs up the inside rear wall of the basin. If any of those flaps are damaged or missing, water will leak out there instead of being directed to the spray arm depending on which height position you're using. If you're lucky, you might still have one usable height position without replacing anything. Otherwise you need a whole new supply tube ($60-100) as the rubber part doesn't seem to be sold separately.
Re:E-Prime – English without the verb “to be” on Wednesday May 26, 2021 @06:01PM (#27296658)
Nice work avoiding the copula there :)
Re:PostScript Language Reference (1999) [pdf] on Monday April 19, 2021 @09:05AM (#26862292)
PDF had support for JS at least since the late ‘90s as part of the scriptable forms system.
Re:Show HN: Array – A Better Python List on Sunday January 10, 2021 @11:20AM (#25716190)
Dask does the lazy evaluation and query planning thing on numpy arrays and pandas dataframes, and can execute in parallel. It mimics most of their native interfaces which makes it a pretty easy drop-in.

https://docs.dask.org/en/latest/

Re:On Repl-Driven Programming on Sunday January 03, 2021 @01:48PM (#25623967)
True, but running the %debug magic command in IPython immediately after an unhandled exception drops you into the debugger at the point of the raised exception, complete with the full interpreter state including the stack. It doesn’t permit edit-and-continue but you can still evaluate expressions (including calling any function) to explore what went wrong without having to recreate the situation inside an explicit pdb session.
Re:No One Wants Used Clothes Anymore (2018) on Friday December 04, 2020 @10:40PM (#25311510)
Yeah, that part of Cambridge was originally all industry. It’s been changing slower than you would think.
Re:A tale from the trenches fixing an NES on Tuesday October 27, 2020 @07:28PM (#24913257)
Shellac has nearly zero resistance to water vapor so it wouldn’t prevent corrosion at all. Nitrocellulose lacquer isn’t a lot better.
Maybe even more so the sequel Syndicate Wars

https://youtu.be/ECHmCzXMFb8

I have fond memories of using Swarm in an undergrad course on agent based simulation ~20 years ago. Just tweaking the heatbugs example in various ways was already enlightening. Thanks for your work!
Re:Woodworking for Engineers on Thursday June 11, 2020 @10:45AM (#23489464)
I’m an American with a very limited space to work in and I love Paul’s approach.
Re:Woodworking for Engineers on Thursday June 11, 2020 @10:43AM (#23489435)
Regarding finishes, I highly, highly recommend the book Understanding Wood Finishing by Bob Flexner. Flexner applies a very no-nonsense scientific approach which greatly demystifies the process. For example he explains what that pre-stain conditioner actually is (chemically), what it achieves (with photos), and exactly when you would want to use it. There is a lot of marketing and folklore around wood finishing which makes it a lot more confusing than it is, and this book helps cut through all of that.
Re:SETI@home shuts down after 21 years on Tuesday March 03, 2020 @07:07PM (#22480014)
The Duron had a set of circuit traces exposed on the ceramic chip carrier that were cut by laser at the factory to set the maximum allowed clock multiplier (and thus its final speed). You could reconnect all the cut traces with pencil lines and use a motherboard that let you set the multiplier directly to overclock freely.
Re:Loading NumPy arrays from disk: mmap() vs. Zarr/HDF5 on Friday February 28, 2020 @04:54PM (#22446776)
Sorry, I thought Feather supported random row access but it turns out it only supports random column access.

For fst, I only played with the R interface, which would be called like this to retrieve row 12345 from the "fingerprint" column:

  read_fst("library.fst", columns="fingerprint", from=12345, to=12345)
However fst didn't offer a raw/binary column datatype last I checked, which is frustrating. It has chr (string) but R can't have embedded NUL bytes in strings, so that was a dead-end for efficient storage of binary fingerprints for R. I didn't check if the underlying fstlib structures accept NULs in string columns.
Re:Loading NumPy arrays from disk: mmap() vs. Zarr/HDF5 on Wednesday February 26, 2020 @09:02PM (#22429674)
Hi Andrew! Looking into similar requirements I came across Feather and fst. They both basically let you efficiently slice into compressed on-disk DataFrames. Feather already supports Python, but fst is just for C++ and R at the moment.

https://blog.rstudio.com/2016/03/29/feather/

http://www.fstpackage.org/ https://github.com/fstpackage/fstlib

And it flat out refuses to run without an internet connection to fetch ads!
Re:Ask HN: Did your AWS bill literally double from last night? on Sunday September 22, 2019 @09:52PM (#21045320)
All those dashboards use the APIs underneath. The cost explorer dashboard certainly does incur API calls on my account.
Re:Fridge Condenser Fans – Old and New [video] on Monday September 02, 2019 @03:23PM (#20861254)
You can fix some freeze-over issues by taking a length of stiff wire (14 gauge solid copper is great if you have some, a wire coat hanger is an OK substitute), wrapping one end tightly around the nearest part of the defrost cycle heater element, and routing the other end through the area where you are getting ice build-up. Some freezer designs allow ice to build up out of the defrost heater’s reach, and the added wire just conducts that heat where it’s needed.
Re:In praise of xlogo on Friday August 30, 2019 @07:18PM (#20843592)
I once used a computer lab where the AIX workstations each had their local filesystems exported to the entire campus via AFS. Even /dev. Including /dev/audio. Which was world-writeable. And there was no apparent volume control for the chassis speaker.
Re:Thomas Edison DC Electrical Cables on Sunday August 18, 2019 @09:05PM (#20734082)
It’s a treasure from the “old web”. Information dense, simple markup, possibly updated by hand...

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