Thu, 30 May 2013
GPS Tracking Systems
I use my smartphone in addition to the cyclocomputer in order to be able to record my speed, and later compare the speeds at the same place amongst various conditions. The problem is what to use for tracking and what for reviewing and comparing the recorded tracks?
So far I record the tracks using Move! Bike Computer on my Android phone. It is far from ideal, but at least it stores tracks as a GPX files which are accessible directly from the flash. It uses 1-second intervals, and as a bonus, it can display the track using Google maps. The drawback is that it sometimes does not switch the GPS on, so it needs to be switched on manually from the Android top bar menu. The other drawback is that while it can send the GPX files by e-mail to the desktop computer, it does not remember the prefered export format (GPX instead of KML for me) and the prefered export method (e-mail using K-9 mail to a predefined address). So sending tracks from my phone for further archivation is not so easy. But at least it can be done. Another problem is the start and end of the track: I usually start this app before leaving home, and stop it some minutes or hours after reaching the destination. The recorded tracks then cannot be easily compared, because their durations vary in the order of tens of percent, even though the real time of activity is roughly the same. The auto start/stop feature of the cyclo computer is much more precise - the GPS always report at least some movement because of its imprecision and noise.
As for the viewer, the situation is even worse. So far the best I have found is Endomondo, (and "the best" here does not imply "good" at all). Endomondo can import the tracks in the GPX format, and display them on top of Google map, can generate the speed and height profile, etc. On the other hand, it is way too skewed to training and fitness (computing calories, etc.), and has way too much useless social features. It also has its own proprietary Android App, which makes sending data to Endomondo easier, but with this app it is impossible to get your own data back in an open format. Moreover, when importing GPX data with 1 second granularity, Endomondo rescales it to something more coarse (tens of seconds to even minutes), so it makes comparing the speed at a given place pretty meaningless.
What do you use for your sports tracking, and how does it meet your data accessibility and openness requirements?
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Wed, 29 May 2013
Apparently at Mall.cz they think that they sell only perfect goods, and don't want people to write negative reviews to some of the goods, even though the description contains plain lies. As an example, we take this 9V rechargable battery. In the description, they say:
The rechargable NiMH battery from GP Batteries lasts up to 5 times longer than alkaline batteries [...]
There has to be some serious magic used by either Mall.CZ or GP Batteries, which causes that the battery rated at 8.4 V with 200 mAh capacity lasts five times longer than an ordinary 9V primary alkaline cell. Apparently the later according to Wikipedia has 565 mAh capacity, and thus stores three times more energy than the rechargable batery from GP Batteries.
I have written a comment along these lines to the Mall.CZ system on May 7th, but it is still not published as of now. So beware of any e-shop which doesn't allow negative comments, such as Mall.CZ. It is interesting that some bigger shops like DX are perfectly OK with people writing negative reviews to some of their goods.
1 replies for this story:
Vašek Stodůlka wrote:
It is possible in some use cases to "last 5 times longer". When you put alkaline cells to camera, they can last as low as 50 shots, but NiMh batteries about 250. Alkaline batteries cannot produce high current very quickly - so technically your comment may be considered as not true. And there is "up to", which can also 0,5x. :-) But if this is a 9V battery, which you put to some kitchen scale, it will last about few months and alkaline can be there for years. But it is still "up to 5x", so they are right. :-)
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Fri, 24 May 2013
The last file manager I have used was Norton Commander back in the DOS era. Many years after that, during the flame wars between proponents of spatial and single-windowed Nautilus, I have only laughed at them, thinking that the command line was much better. Why would anybody need a GUI file manager? I feel slightly ashamed now, but I have to admit that for the last two weeks, I have also been using a GUI file manager.
I work on various things with respect to cabling, electricity, a new datacenter, and so on in the new building of Faculty of Informatics. The problem with the building specifications, projects, and so on is, that they are stored in the deep structure of directories, with names containing whitespace and even non-ASCII characters (in different character sets), and each directory contains many files or subdirectories with common prefixes shared by a set of files. So the usual tab-completion does not help - it is necessary to actually look at the completion prefix in order to know what character to add next. Here is an example of such a file name, starting from my automount point:
stavba_cerit_dok/01_ZADAVACI_DOK/02_zadavaci_projektova_dokumentace/\ FIMU_GD_SOD_příloha č. 1/!!!_02_FIMU_GD_SoD_Priloha_1_II.A_PD_DVD_PROJEKTOVA_DOK_1.etapa!!!/\ FI_F.3_03_PS 03 SUPERPOCITAC, DATOVE CENTRUM_DVD/\ F.3_03_5 SLABOPROUDE ROZVODY_DVD/F.3_03_5.2.01_PUDORYS 5NP - SLABOPROUD.pdf
In order to be able to quickly navigate inside such directory tree, I have started to use a GUI file manager. So far I use Thunar, the default file manager in XFCE. It can easily switch to any directory along the current path, and it has bookmarks for fast access to frequently-used directories. I use this feature a lot, because of the main drawback of GUI file managers: It is not possible to descend into a directory, which is an automount point (and which, from the VFS point of view, does not exist yet).
Do you use a GUI file manager?
4 replies for this story:
Milan Zamazal wrote:
I use Dired in Emacs. Powerful, text based, utilizing common Emacs features (e.g. bookmarks) and excellently integrated with the whole Emacs environment. I don't know how it compares to current file managers but it used to be much more powerful than anything I've seen in the last century. Considering my recent experience with some popular e-mail clients and discovering how primitive they are I've got some reasons to believe there are still not many file managers comparable to Dired. But does it make sense to use Dired without using Emacs generally? Probably not as environment integration is an important part of file manager usage. For instance, it's impractical to have different sets of bookmarks in a file manager and in other applications or it would be annoying if you renamed a file in a file manager and the corresponding change didn't happen in your editor having the file open for editing at the same time.
Yenya wrote: Re: Emacs
Well, the feature with rename probably does not work when the file in question is renamed by something else (possibly over a network FS), altough it can be partially solved with inotify. Apart from that, I don't want to boot another OS just to use a file manager.
I use tc (Total Commander) on windows, and mc (Midnight Commander) on linux/mac, both are very similar to nc. Another plus is that it's not required to have emacs (or vim) to use it ;)
I have to admit that I simply use Nautilus in such cases. And immediately rename them all.
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Tue, 21 May 2013
Cell Phone Operators
Few weeks ago I have moved my cell phone number to a different phone operator (don't ask :-). Today, I've got an interesting call:
Caller: "Hello, I am a representative of $my_new_operator, do you have a minute or two?"
Me (thinking about possible problem with $my_new_operator, with payments, or whatever): "Well, only a minute."
Caller: "OK, then. We have a great offer for customers of $my_old_operator. If you move to $my_new_operator, you can save much money."
Apparently the $my_new_operator's representative does not know that I am already their customer.
2 replies for this story:
Bobby wrote: 360
It is called 360° customer view. They can see everything about you in any of their applications :-)
I had similar experience two years ago (and - I guess - with different operator)
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Fri, 03 May 2013
I've got my laptop, ASUS F3E, in September 2008. So maybe it's time for a new laptop. Last year I have briefly considered buying a new one, but I have found that after upgrading F3E to 4 GB of RAM, 9-cell battery, and a fast solid-state disk (OCZ Vertex 2), then-current models provided no significant improvement compared to my F3E. Is this year's offer better?
There are several problems with my F3E:
- Glossy display (no explanation needed, I think)
- Plastic chassis, which is already broken in two corners
- Slightly slower CPU than needed (I had problems playing full-HD video without frame dropping once or twice, but I am not sure whether mplayer can use both CPU cores)
- The WiFi interface supports 2.4 GHz band, not 5 GHz one
What parameters should my hypothetical new laptop have? Of course, it would need to be better than my upgraded F3E in every aspect, and meet the following criteria:
- Size: less than 16", preferably not smaller than 14"
- OS: sold without Windows (I don't want to pay the Microsoft tax)
- Display: matte, at least 1280x800, possibly with touch input
- RAM: at least 4 GB
- Graphics: supported in Linux using open source drivers, including 3D acceleration (so most probably I don't want nVidia)
- HDD: preferably SSD, but I can reuse the SSD from F3E
- CD/DVD/...: preferably none
- Battery: at least 4 hours with moderate usage
- Keyboard: with long backspace, double-height enter, inverse-T arrow keys, and preferably without separate numeric keypad; backlit if possible
- Chassis: aluminium or similar, definitely not plastic
Does such a laptop exist, my dear lazyweb? Or shall I stay with my upgraded ASUS F3E for another year?
10 replies for this story:
Some time ago I bought Lenovo X230 and I'm ok with it. It has (or can have) everything you described above except of the screen size, which is less than 14", and MS tax. I believe it can be equipped with a 3-band antenna which allows 5Ghz wifi, but in this case you wouldn't have the webcam. Check the specs to be sure. Optionally you can have a backlit keyboard or thinklight. I have even managed to squeeze in a 16GB of RAM and an msata SSD, along with a regular HDD. Battery life is about 5-7 hours with 6-cell battery, but I suspect that the power management in my system sucks. In windows it's much better.
I forgot - you may also check out Lenovo X1 Carbon, it has similar specs to X230, but the screen is larger with higher resolution I think. You can cut your vegetables with it :-).
Peter Kruty wrote:
You are describing mac book air in your criteria :). (If I can take the liberty of ignoring 'preferably not smaller than 14"'.
Yenya wrote: Re: Macbook Air
Is it really supported in Linux with open source drivers, or have you took the liberty of ignoring this requirement as well?
@Peter Kruty: How is paying the Apple tax better than Microsoft tax? You can at least fight that one, I bet there is no chance to get your OS money back from Apple. @Yenya: Why do you have so small requirements for the display? Every other _phone_ has better resolution these days.
Peter Kruty wrote: mac book air
@Yenya: Oh, somehow I assumed this is solved problem for Intel graphics (not really watching this closely). So, yes I took the liberty too. In general looks like so called ultrabooks are matching most of your requirements. @honzah: Yenya was mentioning not willing to pay MS tax (nothing about Apple). Regarding Apple Tax: I believe this is different situation Apple HW and SW are designed for each other and from same vendor. I don't blame Apple for that, because it works very well for usability. Variety of generic laptop vendors are locking their hw to windows, while we can hardly talk about same tight integration for a user's benefit (and I mean a generic computer user, not someone like Yenya with very specific requirements).
Yenya wrote: Re: Macbook Air
Well, I didn't know that Apple uses Intel graphics - this is actually well supported under Linux. That said, even though I did not mention it explicitly, Honzah is right that for me, Apple tax is almost the same as Microsoft tax. Why would I buy a hardware from a vendor which explicitly does not want me to use it with Linux?
Basically, you can have a generic crap with some disastrous 1366x768 display (it doesn't matter if glossy or matte, it doesn't, it doesn't, it'll have faded vomitty colors anyway), they are all absolutely same. Or you can have something more decent, but then, it's either the macbook, or perhaps some more high-end-ish ultrabook.
Peter Kruty wrote: Dell XPS 13
Quite expensive, but you are paying for your specific requirements :) http://www.zive.cz/bleskovky/dell-xps-13-linuxovy-ultrabook-s-ubuntu-dostane-full-hd-displej/sc-4-a-167668/default.aspx
Yenya wrote: Re: Dell XPS 13
Looks interesting, thanks. The specs (even on the Dell site) are shallow, though. No mention whether it has matte display, and how exactly the keyboard looks like. Also, no SD card reader, but I guess this is the price for being so thin. OTOH, I am ok with the cost. But according to zive.cz, it is not (yet?) sold in CZ.