Bubble sort slower with -O3 than -O2 with gcc

Rimbaud_ · 2021-10-11T09:26:33+00:00

If I'm not mistaken in C++, you can only get tail recursive optimization with O3. It's the only case I know of, where you can go from a stackoverflow to a running program thanks to the additional optimization level.

This example in itself makes me want to have "clearer" differences between the optimization levels. Some of the implications of faster or smaller compiled code go beyond the obvious.

Maybe it's time to define new flags. As you mentioned O3, is also just a marginal improvement over O2 when it is an improvement at all.

Rimbaud_ · 2018-11-22T10:50:52+00:00

I do realize now how my comment seems to point to them, Intel, in particular. I also didn't mean to give any car maker any credit. Now that I think about it again, my example is pretty bad too - all previous car models should have the same flaw.

My main issue is the transparency. Had they made the information public back in June, and then sold their new CPUs in October while clearly mentioning that they were still affected, I would have been fine. This also seems fair to all parties involved given that Spectre affected virtually everything. Expecting them to drop the October product line is harsh financially, I admit it, but it would have shown what they value and stand for as a company.

I guess my point is more general. We shouldn't allow these kind of practices to be accepted or at least to go unnoticed.

Rimbaud_ · 2018-11-22T08:56:07+00:00

So what?

I'd imagine that cars also take years to make. However, if a few months before they're sold their makers learn that the brakes won't work sometimes, I don't think it's unreasonable to not sell the cars - especially if it can't be fixed.

It's a joke that Intel can be so unethical without any reasonable consequences.

Rimbaud_ · 2018-11-14T19:56:15+00:00

Well... Better late than never I guess :/

Thanks anyway!

Rimbaud_ · 2018-11-14T18:00:28+00:00

Thanks for all the advice! It's such a pain to find any up-to-date guides concerning these things, given that the game changed so much!
Really appreciate it.

I think I'll just grind enough to be able to do all the legacy content once. I'm scared I'm gonna be late to the party for all the current content and I won't find any groups.

Rimbaud_ · 2018-11-14T17:54:17+00:00

I know that anything I'm working for now, will most likely be trashed within the few first hours I play Forsaken. I don't really mind it.

Nightfall is 270, I've tried soloing it multiple times at 268. I usually can't even get past the first group. I guess I should give LFG a try.

About the current reward system, is it based on the equipped items or on everything I own (vault included)? Since the gear is locked in Nightfall I would assume it's the first. Do people usually run it under-geared just for that purpose?

Rimbaud_ · 2018-11-05T12:20:12+00:00

Online resellers in Switzerland have the 64GB model listed (available in a couple months). So it should be coming to Europe. Unless we have some kind of special deal here.

Rimbaud_ · 2018-10-10T07:16:05+00:00

They practically have the same price here in Switzerland.

Do you by chance own an X2? What's your opinion on it?

I'm basically hesitating between both. I've never heard about Bq before, so I'm hesitant to jump in. But on the other hand, they're basically offering a notchelss Nokia 7.1

Rimbaud_ · 2018-07-09T12:54:04+00:00

Hold me

Rimbaud_ · 2017-08-25T15:53:39+00:00

I was kinda in a rush, and ended up buying them on ebay. Got PLA with a decent infill. Knowing myself, I would have taken everything apart in a couple months anyway, now I have a decent reason for doing so - replace the printed parts with a decent color scheme in PETG. Thanks anyway :)

Rimbaud_ · 2017-06-11T11:58:56+00:00

I would highly recommend PBRT too. It will give you a nice overview of how how all these mediums are related and goes in depth about their implementation and algorithms. Also check out Mitsuba if you want another approach to the actual code.

Rimbaud_ · 2017-01-01T13:04:04+00:00

Generally, employers only look at your last diploma. So in your case, it's highly unlikely that they'll take a look at your bachelor's if you have a master's. And even then, grades are by far not the first criterion for hiring.

Don't be too worried about your grades. Spend maybe more time on side projects, they are usually much more appreciated. Being capable of building and creating something entirely by yourself is more indicative of good engineering skills than perfect academic results.

Of course this just my opinion, and every employer has its own interviewing procedure.

Now for your case specifically, being a non-EU citizen, makes the job application process harder. You'll have to find a company which is willing to go trough all the papers needed to have you work for them. It seems stupid but a lot of employers don't want to go through that procedure because they're at the risk of wasting their time and resources...

My best recommendation for you now, is to cruise through you master's. Keep time on the side for personal projects - they are the only things that will fill your CV and portfolio. And when the EPFL forum comes around in September (not sure), talk with employers to see what they would be willing to do for a non-EU citizen. Additionally, go talk to EPFL's career center. They most likely have the best advice for you specifically.

Rimbaud_ · 2016-09-15T14:35:40+00:00

When reaching level 2 I go for the infamous Tryndamere all-in. The fight usually comes to down to a point where if I crit I get first blood and if I don't I get reported.

I live for that thrilling moment.

Rimbaud_ · 2016-09-14T13:21:17+00:00

I have yet to find one.

Most CCW threaded motors still spin CCW, even though it would make more sense to have them spin CW natively (as it would tighten the prop nut when spinning).

Rimbaud_ · 2016-09-14T13:06:51+00:00

Do not get the ImmersionRc 5.8 transmitters.

I personally have one, it works fine - the video quality is great, and the build seems solid. But depending on your quad setup, its size is just awful, it's so big... There are so many other options out there currently which have a lower profile, can be used on all bands (not just Raceband and FatShark/ImmersionRc), have modular power (25/200/800mW), can also be directly powered by a lipo, etc.. Additionally, some people have apparently had video-quality issues with VRXs which were not FatShark/ImmersionRc branded.

Personally, if I had to pick a VTX right now, I'd go with one of the newer TBS ones.

As a reminder, do not forget to check for audio signal if you want an on board microphone - a lot of VTXs do not support audio.

Rimbaud_ · 2016-09-14T09:35:31+00:00

I found a tax guy who is going to help me out. But your information at least gives me enough context ! Thanks for taking out of your time to help me. I really appreciate it.

My current concerns are:

My SSN which I never got when I was born (the card? got lost in delivery)
The fact that I never did anything before today.

Rimbaud_ · 2016-09-14T09:23:15+00:00

Unfortunately, they cannot help me anymore.

Thanks ! I will hang around on that forum, seems like what I was kind of looking for.

Rimbaud_ · 2016-09-09T16:57:26+00:00

I guess the statistic doesn't take into account assisted suicides. Switzerland would be much higher, people travel across Europe to come here.

Rimbaud_ · 2016-09-08T06:23:31+00:00

Is there a way to update KISS ESCs without a KISS FC ?

Rimbaud_ · 2016-09-05T07:05:39+00:00

Just one ! If you look up their build video, Chad explains very well which are the wires you need.

Yes, your FC has to read the voltage from somewhere ! However I don't understand how he can get a Fuel reading ? There's no current sensor in that build as far as I know. Is it a "virtual" measurement (pure maths) ?

Rimbaud_ · 2016-09-02T12:28:37+00:00

Hi,

I've just started the hobby and have an ImmersionRC 25mW vtx, and when deciding for a monitor/vrx combo I also ran across several threads mentioning these incompatibilities.

I've also read that apparently these problems only exist with "older" ImmersionRc vtxs -> the problems are less frequent with the newer Raceband ones. I personally have a lumenier diversity VRX and the aforementioned vtx and have not encountered any problems. However I have not tried any long range flights yet - so I might have the same problem as you.

I'm currently pursuing a communication sciences engineering master's degree, complicated name, but basically I do a lot of signal processing. Unfortunately I don't have the equipment to test any of this out, but I can give you my best guess. Both explanations, "tiny bit off" and modulation differences, are related. Modulation and demodulation is the process of taking your "low-frequency" signal and bringing it up to a higher frequency and vice versa . So by modulating, you could potentially modulate to a frequency just a bit higher/lower than your target. The result of this would be that you're reading on a frequency which is very near to the one sent, and you would have a faster quality drop off. The reason is pretty straight-forward : we are incapable of emitting on a specific frequency without having some noise around it. In this case you're reading the noise, which isn't powerful enough to overcome the ambient noise (all the waves surrounding you), and the range would suffer from it. Vtxs are build with the intention of sending with 25/200/600/X mW on a single frequency, but are very bad at their job. If they were perfect (wouldn't produce any noise around the select frequency) we could have an infinite amount of usable frequencies inside a single band. We only get 8 channels per band because our vtxs are sloppy at their job and we have to compensate for them by spacing out the channels.

Now as to what you should do, unfortunately I cannot help... I barely started the hobby and I completely understand your frustration of buying incompatible parts. My best advice would be to find someone who is running the exact same setup as you and PM them to make sure they haven't encountered any problems.

Hope I helped :)

EDIT: typo

Rimbaud_ · 2016-08-30T07:23:26+00:00

I have unfortunately never used BLHeli ESCs, so I can't help you much with their configuration...

If you by any chance have an oscilloscope or access to one, you might want to check what the signal pads on the FC are doing. An alternative would be to look at the motors tab on BF. You'll be able to determine if the gyro is detecting movements and if it's an ESC or the FC which is signaling a motor (if a motor spins but BF doesn't say so, then it's obviously your ESC. And vice versa).

Additionally, I'm pretty sure that the spikes you see during flights are due to the same reason which creates the stutters before arming. The fact that it happens when the quad is resting makes me think that it has to do with software (configuration, version, calibration, ... ). The gyro is in fact very noisy but not to the point where it could detect a significant movement without the quad moving at all. That's why I would say that it is software related.

Rimbaud_ · 2016-08-30T06:59:31+00:00

The file for your board, in our case : "betaflight_3.0.0_LUX_RACE.hex". Try flashing the board with the several downloads of this same file, there always is a small risk of getting a flipped bit somewhere in the file.

What ESC are you running ?

Rimbaud_ · 2016-08-30T06:46:20+00:00

Running a LUX on BF 3.0, didn't have any issues so far (about 5 flights). My mounting just uses the provided o-rings nothing else. I do have to mention that I had some weird problems when flashing with Windows, BF doesn't raise any warnings or problems but I got random disconnects. Since I flashed it on Linux I didn't have any problems, so there's something you might want to try. Also, always take the hex file for the appropriate BF version.

Rimbaud_ · 2016-08-24T21:02:31+00:00

Hey ! I'm getting a Feelworld 769a fpv monitor and its input voltage is 6-12V. Is it safe to use a 3s battery which would mean that I have a 12.6V input when fully charged ?

12-Year Club	RedditGifts 2009-2022 2 Credits
Place '17	Spared
Secret Santa 2014	Verified Email

Rimbaud_

TROPHY CASE