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m3koval

151 karma · joined December 13, 2010

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m3koval··on ESP32 Buyer’s Guide: Different Chips, Firmware, Sensors
It should be possible to do that using one Ethernet port using VLANs. You could buy a cheap L2 managed switch and use it to trunk two different Ethernet networks on the same port. Then you would configure the Linux networking stack to split the VLANs into separate interfaces.

I am by no means a networking expert and was able to use technique to work around a similar issue in the past. It was easier than I expected!

m3koval··on Parse, Don't Validate (2019)
SIGBOVIK is a parody of computer science conferences. It's a running joke hosted on April Fools Day every year at CMU - and apparently a quite convincing one. ;-)

Source: I attended SIGBOVIK a few times in grad school.

m3koval··on Google’s Self-Driving Car Project Is Losing Out to Rivals
As someone who lives in Pittsburgh - and likes the city quite a bit - I can attest to the fact that: (1) the weather is rarely perfect, (2) the entire city is under perpetual construction, and (3) the lines have not been painted in years. It took me quite some time to comfortably drive in the city because to the narrow streets, poor road maintenance, and bizarre traffic patterns induced by the many bridges and tunnels.

It will indeed be interesting to see how the well the Uber deployment goes in practice. They certainly did not choose an easy place to start.

m3koval··on Introducing C++ experimental io2d (2D Graphics in the C++ standard library)
Concepts, modules, a file system library, and an asynchronous I/O library have all been discussed as additions for C++17 and beyond. Most of these features are standard in modern languages. I would not consider any of these to be "scarcely useful." As someone who uses C++11 on a daily basis, I very much look forward to using these features without a Boost dependency.

That being said: I don't think that a graphics is a good addition to the standard library. It would tremendously difficult to standardize this for the reasons others have mentioned.

m3koval··on Ghost in the machine: screen contents across reboots in a Macbook Pro Retina
I had this issue fixed on my mid-2012 15" rMBP. It's known issue with some of the early LG panels on that model. The technician at the Apple store ran some standard image persistence diagnostic script to replicate the issue.

They replaced the display for free outside of AppleCare. I didn't have to argue with them at all, so I suspect that this is their standard response. YMMV if you have a newer model.

m3koval··on Code that will break in Python 4
C++ is not technically a superset of C. Here are a few examples that are valid in C, but not C++:

http://stackoverflow.com/a/1201840/111426

However, it's close enough that I generally agree with your point.

m3koval··on Strange C Syntax
The bitfield example is misleading. Section 6.7.2.1/10 of the C99 standard says:

"The order of allocation of bit-fields within a unit (high-order to low-order or low-order to high-order) is implementation-defined"

There is no guarantee on the order of the bits inside a bitfield. The compiler may also introduce padding, e.g. for alignment purposes. This makes bitfields unusable for unpacking binary data.

Unfortunately, you're stuck with shifting and masking to replicate the same effect.

m3koval··on Dijkstra’s algorithm and the Fibonacci heap
Why would you not use A* from the beginning? It's a trivial extension to Dijkstras and is often orders of magnitude faster when an informative heuristic is available.

Also, both algorithms require identical data structures. After all, Dijkstras is just A* with a zero heuristic.

I do agree about the constant factor, though: it's likely that a binary heap would be faster on most data sets.

m3koval··on Solving a Combination Lock Puzzle with JuMP and Julia
Unfortunately not. Matrix inversion (or any type of linear algebra, really) deals with real numbers. This problem is nearly a linear program, which can be solved very efficiently, except that some variables are constrained to { 0, 1 }. As a result, it's an integer program, which is NP-hard. Intuitively, this is hard because there are no derivatives (e.g. gradient, Hessian) to exploit in discrete optimization problems.

One heuristic is to solve an IP is to relax the integer constraint to inequality constraints, solve the LP, and round the results. However, this can do arbitrarily poorly on most problems.

m3koval··on Lavabit Founder Says He Had ‘Obligation’ to Shut Service
Nope. Maybe it used to be true, but not as of 2007.

"…prohibits you…from disclosing this letter, other than to…an attorney to obtain legal advice or legal assistance with respect to this letter.""

Source: http://upload.wikimedia.org/wikipedia/commons/9/91/EFF-IA_Na...

m3koval··on 1912 Eighth Grade Examination for Bullitt County Schools
Nit: You can't, by definition, prove an axiom. Memorizing axioms is quite necessary because they are the building blocks for all other theorems.

In any case, I don't disagree with your high-level point.

m3koval··on Matlab is oversold as a general-purpose language
Matlab is much faster. For a sense of scale, a relatively simple image processing script ran 125 times faster in Matlab than Octave. This is, most likely, because Matlab has a better code optimizer.

I don't see a compelling reason to use Octave unless you're trying to avoid paying for a Matlab license. If you're going to switch tools, why not switch to NumPy/SciPy and get the advantage of using a full-featured programming language?

m3koval··on How do the state-of-the-art pathfinding algorithms for changing graphs differ?
Like antics said, this isn't true for graph planning. Here are three concrete examples that I know of:

1. Anytime D* was used by the winner of the DARPA Urban Challenge

2. Field D* was used by Spirit and Opportunity on Mars

3. ARA* (and other A* variants) are a method of optimal motion planning in robotic manipulation

m3koval··on Introduction to Competitive Programming Contests
It's not that uncommon in CS. I just started a Ph.D. program (Robotics at CMU) straight out of undergrad and a decent number of the other incoming students are in the same boat. It varies depending upon the field and the university. For example, several of the top mechanical engineering programs require a M.S. to apply for the Ph.D. program.
m3koval··on Fabrication Trick Offers Fivefold Leap in Hard-Disk Capacity
I doubt it. The article makes this sound pretty specific to producing the magnetic disks used in hard drives. I don't see any reason why this would also work for silicon processes.
m3koval··on First High-Resolution Color Mosaic of Curiosity's Mastcam Images
Just a guess: The weaker gravity (around 1/3 of Earth's gravity) makes it much easier for wind to pick dust off the ground. Once a dust storm starts, it would also take a lot longer for the cloud of dust to dissipate.

Look at the videos of astronauts on the moon from the Apollo landings. Everything they do kicks up a significant amount of dust that takes quite a while to dissipate. Obviously it's not a perfect comparison because the moon has weaker gravity and a different composition.

m3koval··on The IPS LCD Revolution
That description states a resolution of 1920x1200 instead of the 2560x1440 on these panels. I think 1920x1200 looks pretty awful on a 24" monitor, so I'm sure it will look even worse on one that is 3" larger.

It's a shame these monitors don't have an HDMI input. Then again, I can't complain given the price.

m3koval··on Is it unethical to quit just before a project?
He was being sarcastic (I hope).
m3koval··on Facebook to Launch Job Postings Board
Depending upon how this evolves, it could cause legal issues for employers who make postings. It's illegal to discriminate by a lot of personal information such as nationality, age, race, whether they have children. All of this information is quite obvious when you look at someone's Facebook profile.

IANAL and don't know enough about employment law to know if this is a legitimate concern. It doesn't sound like this is a very serious effort ("Facebook had a third-party developer create the new site"), so maybe there's nothing to be worried about.

m3koval··on Google Shutdowns Continue: iGoogle, Google Video, Google Mini...
I personally don't see the point in iGoogle, but it was perfect for a certain demographic. Anecdotally, I know of quite a few middle-aged people who learned to use the internet when portals were king. After Google surpassed Yahoo, they simply switched to iGoogle.

Even with Google Reader, RSS feeds aren't very easy-to-use for non-technical people. It's going to be interesting to see how they adapt now.

m3koval··on Thunderbolt to Gigabit Ethernet Adapter review
It doesn't fit. The RJ-45 connector nearly the same size (possibly larger) than the edge of the retina MacBook Pro.
m3koval··on Talk Of GCC 5.0 To Be Modular, More Like LLVM
On OS X, you get clang and llvm-gcc in XCode 4.1, which is a solid 1.4 GB download. You're absolutely right about clang being pretty lightweight, so it's getting a bad wrap by association. I'm honestly not sure why XCode is so large: perhaps the IDE and iOS simulator?
m3koval··on Apple releases Ipad 3
Apples call it the "iPad 2" on their online store.

http://store.apple.com/us/browse/home/shop_ipad/family/ipad

(look at the bottom of the page)

m3koval··on Show HN: Using a color pattern to let a user 'recognise' their password
I hate requirements like that. My hunch is that they the SE team hasn't put a ton of thought into the account creation process because they also support OpenID. I didn't even realize that you could login to StackOverflow without using OpenID!
m3koval··on Electronic Arts bringing back ‘SimCity’ franchise after 10-year absence
I never thought about SimCity (or any city planning game, really) on the iPad. In hindsight, it seems like a great idea. Most of the game is placing long strips of transportation and utilities, like power lines and roads, or zoning large areas. Both of these tasks are well-suited for a touchscreen display.

Unfortunately, it sounds like it will be PC-only (or PC/Mac, depending on which article you believe).

m3koval··on NASA considers manned outpost around moon to control robots on lunar surface
Nothing is cheap about autonomy, especially when there is limited computing power on-board the robot and power consumption is a major constraint.

Using a hybrid remote operated/autonomous approach is reasonable, though: only send high level commands to the robot. These commands require less bandwidth and are less impacted by latency, so it's the best of both worlds. I believe NASA already does something like this on the Mars rovers by allowing the operator to specify waypoints and letting the robot plan their own paths between the waypoints.

m3koval··on Google at GitHub
None of the projects are forked (at least as of now), but thee are quite a few people watching them. That's not really surprising, though, because it seems perfectly valid to watch a project while waiting for the first commit.
m3koval··on OSX Lion in CSS3
Same problem here. It showed up again after Command + Tabbing out of Chrome and switching back in. It's humorous that the custom cursor fails in the one case where it's identical to my default cursor.
m3koval··on Windows to Mac to Windows to Mac to... Linux? It doesn't matter.
Can you suggest a good Illustrator alternative for Linux? I've tried a few and was never satisfied largely because the GUIs were very difficult to use. Perhaps I tried the wrong ones!
m3koval··on FIRST Robotics Competition kickoff live stream (10:30am eastern)
I was just at a kickoff event in NJ as a mentor as well. Do you mind sharing which? I was at the one hosted by Montgomery High School.
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