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29 dni temudiscuss

I've still got mine. It's been well used but is hanging together still.

10 miesięcy temudiscuss

Seems like another way to deliver nukes to targets...

11 miesięcy temudiscuss

Under uClinux, executables can be position independent or not. They can run from flash or RAM. They can be compressed (if they run in RAM). Shared libraries are supported on some platforms. All in all it's a really good environment and the vfork() limitation generally isn't too bad.

I spent close to ten years working closely with uClinux (a long time ago). I implemented the shared library support for the m68k. Last I looked, gcc still included my additions for this. This allowed execute in place for both executables and shared libraries -- a real space saver. Another guy on the team managed to squeeze the Linux kernel, a reasonable user space and a full IP/SEC implementation into a unit with 1Mb of flash and 4Mb of RAM which was pretty amazing at the time (we didn't think it was even possible). Better still, from power on to login prompt was well under two seconds.

11 miesięcy temudiscuss

Out by a factor of five or more.

A $1 Linux capable ARM: https://www.eevblog.com/forum/microcontrollers/the-$1-linux-...

I'd expect that there were even cheaper processors now since it's eight years later.

11 miesięcy temudiscuss

I used decNumber in the WP 34S project (https://sourceforge.net/projects/wp34s/) and more recently in the C47 project (https://47calc.com).

You are correct in that the decNumber library doesn't support trig operations. Arithmetic, log, exp and square root plus rounding and some conversion functions.

My experience is that decNumber is generally slow. Logarithms are especially slow. Intel's decimal library is much faster & as you noted, it uses binary operations to start it's algorithms.

w zeszłym rokudiscuss

It might be shorter to do some multiplications:

0x08C0C166 = 2⁴ × 3 × 5⁵ × 11 × 89 + 1 = 10⁴ × 3 × 5 × 11 × 89 + 1

Plenty of values that can be reused (11 = 10 + 1 and 89 = 10² - 11).

Still, there is quite a bit of manipulation required and only 17 instructions to do them in.

w zeszłym rokudiscuss

The initial XOR instruction isn't required, registers are zeroed as per the problem statement.

w zeszłym rokudiscuss

Better check his pockets on the way out :)

w zeszłym rokudiscuss

I think there is a spurious "and H" in the title :)

w zeszłym rokudiscuss

Later uClinux was available on m68k platforms without memory managers. The approach taken doesn't seem close to the one in the article.

I managed to put in shared execute in place library support, the limitation being the number of shared libraries rather than what they supported.

2 lata temudiscuss

My favourite mathematical problem looks to have been solved.

2 lata temudiscuss

There is a second issue with the code. The calculation of the mean isn't numerically stable. Instead use:

mean_power = mean_power + (power - mean_power) / count

2 lata temudiscuss

Algol 68 was to Algol as C++ is to C: trying to do too much resulting in over-complexity.

The two page spread showing a graph of the implicit type conversions was a masterpiece.

2 lata temudiscuss

Kind of like the "install this software" as part of the interview process.

"My hourly rating for figuring out your bug is $X".

2 lata temudiscuss

A division free integer in a range RNG has been developed: https://github.com/apple/swift/pull/39143

2 lata temudiscuss

What a crazy idea.

Cost to orbit is huge. Power availability will depend on pushing enough solar up there. Data centres use lots of power.

Getting rid of excess heat is a major problem in space and data centres generate lots of it. Terrestrial cooling is trivial in comparison.

Hardware obsolesce will be a major hurdle as will repairing stuff that fails.

Radiation is a significant problem in space. Shielding will be very heavy or the hardware will have to be build tolerant which is much more expensive and results in a much slower solution.

Much easier and cheaper to install lots of solar and batteries in the middle of a sunny desert somewhere really cheap and build your data centre there. Then build fibre connections to wherever.

2 lata temudiscuss

Every time I've seen similar done in the past, it has come back to hurt the instigator.

2 lata temudiscuss

We're all upside down here and the blood rushes to our heads.

While living in the antipodes gives most of us genius level intelligence, it also prevents interpersonal relationships.

It's a trade off unfortunately.

If you live down under and want more friends, you need to do head stands for long periods to reduce the over oxygenated brain symptoms.

2 lata temudiscuss

This is the easiest way to go but it's only obscuring the GUID. Format preserving encryption (FPE) would be another possibility if it's not simply a byte string.

2 lata temudiscuss

Is California one of the more progressive states with regards to reductions?

This does not bode well for the world we share.