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jmuhlich

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jmuhlich at bitflood dot org

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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.

BioModels 3 years ago

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...

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.

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.

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.

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.

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.

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.

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.

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.

In praise of xlogo 7 years ago

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.