altivo: Geekish ham radio pony (geek)
The tornado watch reaches all the way up to here, though all we've had is rain with a little thunder. Looks like Texas and Oklahoma are taking another plastering though. I heard a storm expert on the radio at noon saying that this is already the worst tornado season for fatalities in the US since 1953. In fact, it will take only another 19 deaths to surpass that year.

Ultra-geeky computer stuff under cut (SFW) )

[Edit May 26] Just a postscript. Replacing the CR2032 coin cell did the trick. Everything is back to normal.

Dye photo

Aug. 25th, 2010 10:21 pm
altivo: (rocking horse)
Here's the promised photo of the dyed yarn. The skein on the left is "before" and shows the natural white of the Rambouillet wool. The two on the right were mordanted with alum and tartaric acid, then dyed with goldenrod flowers. The color doesn't wash out and is certainly bright.

Goldenrod Dyeing


I have three skeins of white wool remaining, and plan to dye them with black walnut hulls, which give a rich reddish brown color. Then I will use the two colors together in a project, probably a hat and scarf or hat and mittens.

Computer booksFor anyone more curious about the book shelf than the yarn (as even I might be in many cases) here is a picture showing most of the books (click for larger view.) The case is one of four that Gary made for me back when we lived in Chicago. He very nicely unhitched them from the walls in my study there, cut them down by one shelf height (our house had higher ceilings there, having been built in 1877 or so) and reinstalled them in my study here at the farm. This one holds mostly computer books on various architectures, languages, and operating systems. And yes, I've read most of these.

Going down to 49F tonight they say. First time below 50F in months if that actually happens. I expect fog in the morning, even though things have been fairly dry here for a week or more.

Rain, rain

May. 1st, 2010 09:56 pm
altivo: Wet Altivo (wet altivo)
But it isn't raining. They keep telling us that it is, or it will, but the sky is clear here.

Wasted part of the day geeking around with the computers. My brief foray into Microsoft's 8-bit FORTRAN from 1983 this week left me curious. I ended up with two test programs running on CP/M and written in Fortran-80 (Microsoft's name for what was really a FORTRAN 77 compiler.) One uses the Monte Carlo method for approximating the value of PI. The other calculates a table of square roots using two different methods and prints the results in two columns so the values can be compared easily.

I modified both programs slightly so they would run on g77, the FORTRAN compiler from the Gnu project. The main issue was just the file OPEN statement. Then I remembered that the DEC Alpha was once considered a premier scientific machine with enhanced math libraries. I do have FORTRAN installed on my Alphas, so why not? I ported the programs there as well. All three environments were fairly close in speed on the square root table. The 8-bit processor was a bit less consistent, showing some variations in the fifth digit after the decimal, but that's still a lot better than a slide rule and the speed was amazing. The Gnu compiler running on Linux seemed fastest, but that may be subjective, and especially so since the Alpha was communicating over an Ethernet link and hub to get to the Linux display.

The Monte Carlo program showed more variation. The 8-bit processor definitely became draggy when the last thousand or so iterations (of 10K) were reached, but it still delivered results to match those of the 32-bit Intel/Linux combo, and even the 64-bit Alpha with OpenVMS. Speedwise, the Alpha and the Intel seemed to be in a dead heat on this.

Does it matter that a 27 year old FORTRAN compiler for an 8-bit CPU environment can still stand up to today's equipment? Perhaps not to most, but I find it interesting or even encouraging.

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