Hacker News Reader

Comment by geertj | Hacker News Reader

Why linear algebra? Honest question, i have not seen this as a specific requirement before.

It can be inferred that they’re making satellites, or at least satellite components. It’s pretty likely that vector math will be involved in some of the software being written in that context. In particular, if anything they write involves navigation (which is a lot of things when it comes to satellites, from actually maneuvering to observation correction) you need to have a pretty good understanding of linear algebra to write good software. And aerospace isn’t an industry where you want someone relying on google for mission-critical logic.

Sure, but there's a huge spectrum between "mild competence" and "can recite strang's verbatim". My experience is that companies emphasizing specific math skills beyond normal professional baselines typically expect the latter despite usually offering the same (or lower) salaries than the former.

strang's would be something that is entry level in terms of linear algebra.

I think they should clarify whether they want somebody that has passed a linear algebra class with high marks based on something like strangs' entry level book before...or are on the cutting edge of graduate level linear algebra research. It's not clear from the post and I suspect that might be an issue.

Give me a couple months and I could recite strangs entry level textbook. I passed that class with an A+. But I could not become a PhD level maths student with a linear algebra research focus in that amount of time.

There are multiple very different ways to interpret a requirement for being competent in linear algebra.

Knowing everything covered in strangs introduction to linear algebra is actually quite low on the potential list of requirements and could be self studied.

If you need a specific specialist degree (like a PhD in linear algebra), then that's just the professional baseline knowledge I already mentioned.

When I last read Strang's, my course included a lot of spectral theory that was decidedly not introductory regardless of what the title says. Either way, the point is that most non-specialist practitioners don't need that. How often have you truly run into determinants mod N or stochastic matrices in real life?

It sounds like our linear algebra classes were somewhat different though. No one received an A in mine. I had one of 3-4 B's.

Never ran into modular determinants IRL but stochastic matrices are pretty common in many jobs - that said honestly anyone that's actually good at linear algebra and dev work has some pretty good options in many fields so considering it as a baseline unremarkable requirement is uncalled for, I agree.

> Give me a couple months and I could recite strangs

Yes, most people had LA classes during college. But would you take a couple of months to relearn something that would be used only to interview for one job that you have no idea you'll get? That's certainly a reason why few people want to interview there.

I would argue that, if the sole differentiating requirement is “must be proficient at linear algebra” (at an undergraduate level), the pay requirements shouldn’t be that different from most other similar jobs. Almost every engineering job will have some domain specific requirements; would you say a job asking for applicants to be “proficient in undergraduate-level fluid dynamics” would require higher pay than any other chemical engineering job? Or, back to SWE, if there’s a requirement to have experience working with microcontrollers, should that job pay more than any other C developer position?

If an SWE job posting has a narrow set of requirements, none of which require particularly high-level education, that means the ideal candidate is a “regular” SWE with experience or knowledge in the field being hired for. It’s not like this aerospace company wants someone who is an expert at linear algebra while also being a full stack dev with intimate understanding of a few major cloud platforms’ offerings and knows how to write windows drivers and does silicon design in their spare time. They’re just looking for a particular type of developer for which there simply may not be any candidates. Yeah, technically you could triple the salary and steal employees from other companies who weren’t looking for jobs, but the economics of that aren’t feasible. If there are n positions and n-a total eligible developers (for some positive a), it doesn’t matter how much you increase pay, there still aren’t going to be enough people to fill the roles. And you’re eventually going to run out of money, because you usually can’t just triple the price of your products.

Satellites go in circles and need to point at things.

Reply on news.ycombinator.com