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Comment "mostly interested in high reliability"== ECC RAM (Score 1) 237

If you are interested in reliability of the results you produce, read on.

If you want trustworthy calculations or documents without occasional random mistakes in content, you need a machine with ECC. See http://www.intel.com/content/dam/www/public/us/en/documents/technology-briefs/workstation-ecc-memory-brief.pdf

Soon to be available:
Lenovo: http://www.anandtech.com/show/9503/lenovo-launches-new-p50-and-p70-mobile-workstations-with-first-mobile-xeon-chips
They do not appear yet on Lenovo's shopping site.

HP: http://www8.hp.com/us/en/hp-search/search.html?nores=true&qt=zbook%20ecc
Results for “zbook ecc” (0) No results found in All HP.com. Please try again.

Nowadays, with very few exceptions, desktop PC's, laptops, notepads, phones and even low end servers all come with RAM that does not check for soft errors at runtime, and usually not even hard errors at power-on or reboot. No parity checking, no Error Correcting Coding (ECC). Most user-class processors, chipsets, motherboards, and BIOS's do not support it.

On these computers, if a random change happens to a bit of code, if you are fortunate, the program crashes. If a random change happens to bits of the kernel, if you are fortunate, the whole OS crashes. If it happens to your application data, well, it isn't what it used to be. Random alterations to a dirty disk buffer in memory will get written out to disk. If it happened to your data, it changed. If it happened to a directory or file system allocation bit map, some spot that is occupied will maybe appear to be free. If it happened to the table of which dirty disk blocks are where in memory, then data blocks on disk will end up with totally content, with the correct content written someplace else or not at all..

Why is it this way? The story goes back 25 years, when clone makers came out with IBM PC clones without parity memory. IBM's and some other company's PC's had parity memory. The good news was that it would catch soft errors. The bad news was that when BIOS caught a parity error interrupt, it cleared the screen, put a Parity Error message on the first line and halted the computer. Unsaved work? too bad. In the middle of a file write, directory or FAT file system update? too bad. Some manufacturers offered a BIOS option to disable that behavior. Enough customers preferred that option that more companies started using non-parity memory. After all, the parity memory bits add another 12.5% to memory cost. Why not be able to offer a lower price for what the customers want? Eventually, even "market driven" IBM started doing the same.

ECC watches for and corrects soft errors when they happen.

For some people, it may be adequate to use a generic laptop to VNC or RDP into a server class machine with ECC for important work.

Comment Not that there was no race. There was. The US won. (Score 1) 295

From all the text in the original item and Forbes blog, there definitely was a race. Several races, in fact. Aryans, Jews, Italians, Mixed-ethnicity Americans, etc, as well as the race for the bomb. Thank God, the Germans did not win, or come close enough to create lots of radioactive material with which to blitz England with dirty bombs and V2's. They might have been set to explode at 150 .. 1000 meters to pollute and require effort to clean up.

Comment A hypothesis cannot act. (Score 1) 107

Proper use of the scientific method may prove or disprove a hypothesis.
A widely publicized hypothesis might cause mass hysteria while being neither proven nor disproven.
Could "A hypothesis of panspermia" "act as the delivery system for alien biology to hop from one star system to another" ?
NO. Any "delivery system" requires instantiation of a mechanism, which might follow from a provable hypothesis.

Comment Re:Infinity (Score 1) 1067

In APL, 0/0 is a null vector. In APL the "/" symbol is the dyadic select operator. The left side is a binary scalar or a binary array with the same shape as the right side. The result has the elements of the right side that had 1's on the left side, or in the case where the left side is a scalar, if it's a 1 you get everything from the right, or if it is a 0, you get a null vector.

You might have been thinking of 0÷0. Where ÷ is the division operator U+00F7

Comment Digital Native == born with count(digits) > 0 (Score 1) 553

I was born with 10 digits. Doesn't that make me a digital native?
My sixth grade science fair project was a 1 bit adder made out of a battery, wire, two DPDT relays, switches, and lights. Does that make me a "digital native"?
Place me among 1964's digerati? biterati?
How about that everyone in my 10th grade learned FORTRAN on our school's IBM 1130?
Fortunately for me, I needn't care.
Sadly, others do.

Comment If code & data fidelity & valid results im (Score 1) 385

If code & data fidelity & valid results are important: ECC (or at least parity) memory is required.
Sadly, I don't know of any laptop or notebook computers, even in the "workstation" class, that support ECC memory.
For serious work, keep it on a machine that supports ECC. Then VNC into it. VNC sends keystrokes and mouse mickeys from the user and sends back pixels from the target machine. That way, if a keystroke gets mangled in transmission, wrong pixels will be displayed and, hopefully, noticed.

Occaisonally Dell, Lenovo, and distributors such as TigerDirect have good deals on low-end servers with ECC, typically with quadcore-no-hyperthreading single socket Xeons. Caveat emptor: Just because a processor, memory controller, and motherboard support ECC memory, that doesn't mean the system assembler is providing it. Verify with the seller; make sure it is specified in the purchase order documents; check when you receive it.

Comment Almost anything algorithmic expansion creates is (Score 1) 85

My understanding is that: Almost anything that algorithmic expansion creates would be in the realm of being obvious to one knowledgeable in that domain. Everything in that category need not be specified in the patent application and is not patentable separately. That means that including those variations is (1)unnecessary, (2) not helpful, and (3) merely adds cost to the patent.

Caveat lector: "My understanding is that," are "weasel words" that indicate I am not a lawyer and I am not giving legal advice and that I am enunciating my understanding, which could be totally incorrect.

Comment environments, team, & domain matter (Score 1) 232

The execution environment matters if the application runs in one.

Execution size & time matter if execution will be long or done many times, or in a constrained environment.

Compile time matters if it only has to run once. That's why there was WATFIV.

If there are any, the standards of the team or organization that produce or consume the source code matter.

Readability and maintainability sometimes matter. I did a lot with APL, including enhancing a program where the flow chart was over 40 pages, but the program was so well structured, it was easy. In most personal programming cases, however, any complex function had to be written and tested in one day. After that, it was almost undecipherable, even by the author.

Verbosity matters to poor typists. It gets in the way of understanding. Did the person who came up with, "Blah blah = new Blah;" stutter? In what way is groovy inferior to java?

Domain really matters. Once I needed something to generate several drawings for a patent application. I considered generating SVG, I considered macro capabilities in a CAD package. In less than a day, I learned and made the diagrams with MSLogo. If I had to do it again, I might use python turtle graphics, but it would have been more verbose..

Submission + - Finally: Electronics & Media Accelerated Burn-in at Home (biglots.com) 1

dakra137 writes: Big Lots stores are now offering the ideal product for accelerated burn-in, or at least heat stress testing, of electronics and media such as DVD's, vinyl records, tape, floppies, Edison wax cylinders, etc. http://www.biglots.com/p/60-media-fireplace
Warning: This item appears to be unvented, so it is not suitable for media destruction.
This has to be one of the world's worst product ideas ever.

6 Curses = 1 Hexahex