Recent content by rcgldr

At my first job in 1973, on a multi-computer multi-tasking database server using HP 2100s, the system had the advantage that it was offline from 3 am to 7 am each day allowing for offline backup. During that time, every disk pack was backed up to another disk pack (there were 10 drives, so 5...

Putting this into perspective. In 2001, quantum computers were able to factor 15 into prime numbers 3 and 5. As of 2025, they haven't been able to factor 21 (without the equivalent of guidance or pre-existing knowledge).

Do web search for "banks required to use decimal math in the US", and you will find explanations. I'm aware that the government institutions that monitor the banks have matching calculations that require the rounding of decimal numbers be consistent between banks and the monitors, but can't find...

In 2001, the U.S. Securities and Exchange Commission (SEC) mandated "decimalization" for all U.S. stock markets (xx 3/4 becomes xx.75). In the US in 1792 the coinage act established decimal currency. The main issue is decimal fractions like 0.1 can't represented exactly with binary floating...

Current Macs are using ARM M1 and M2 processors (an ARM processor is essentially VHDL that becomes part of the main chip that also includes the GPU (graphics processing unit) and other stuff). Apple no longer makes desktops. They make all in ones that include the main board in the monitor and...

Financial institutions are required by law to perform the math in decimal. Cobol typically does this using packed decimal (BCD). This dates back to the days when Grace Hopper and team developed the Cobol language. Prior to that was plugboard programming (unit record processing) that was also...

I have about 25 Windows console mode X86 64 bit assembly only programs, generally math oriented stuff.

In the case of RISC-V, they've added Galois field instructions to speed up erasure code (RVV), and some have pre-fetch instructions. This is a currently active project at github Intel ISA-L: Intel ISA-L riscv64

X86 instruction set is a moving target. As suggested by others, start off with what a C compiler generates. Advanced stuff like AVX512 + GFNI (Galois Field New Instructions) isn't something most programmers will ever get involved with.

I started programming in 1968, using punched cards. There were several batch editors for text files stored on a disk drive at the companies I worked for. The first well known text editor I used for programming was WordStar, which was popular for CP/M programmers...

Getting back on topic, in the case of a static Venturi, as the tube diameter decreases, pressure energy decreases while kinetic energy increases. In a real world situation, the total energy decreases due to losses, but kinetic energy can be increased. Indy and Formula 1 race cars use Venturi...

I agree. I'm waiting to see if someone wants to move all the glider related posts to another thread. If they just want to delete them, I wouldn't have an issue with that either, but don't know about the others involved. I did go through and did strike-through on my prior posts.

I'm still wondering about the horizontal component, especially if you consider the earth's surface to be frictionless, in which case, there could be a continuous change in the horizontal component of air velocity until the glider lands. If the earth's surface is not frictionless, then a...

I agree with this, if someone is willing to take the time to do this. I wouldn't mind a restart on the earth glider system, especially for a glider based frame of reference versus gravitational potential energy. I'm also thinking that the best example of Bernoulli at the molecular level would...

You're correct. I deleted that post (brain fade on my part). I don't recall where I got those images from. There would be a decrease in energy: Δ v would be angled more forwards, and | v + Δ v | < | v | (using | ... | for magnitude). Getting back to the glider in a steady descent, using the...