I'm looking at analysing the quality of area learning with project tango. Is there anyway to save the results of the ADF inspector (quality and number of successful matches) or another method of obtaining results of how effective the area learning is?
Currently, there's no API to let you query the quality of ADF. But you can sort of derive the quality of ADF based on user's movement. If user has observed all directions of environment, then you could consider the ADF is somewhat decent.
Unity AreaDescriptionManagement example shows how to achieve that from the application level.
Related
I am working on a smartwatch project. I want the display to be turned off and only come on when the user brings his hand into the watch-viewing position.
I am running my application on the NRF52 MCU which means machine learning is out of the question. I am using a 3-axis accelerometer from STM.
How can I detect when a user moves his hand into the typically watch viewing position? How is this achieved in smartwatches?
I have the following ideas so far:
- Constantly poll accelerometer and calculate pitch and roll values. Then determine what range of pitch and roll values corresponds to this gesture. This seems a bit wasteful because the CPU will have to be always active.
Is there a simple signal processing algorithm or something similar that can achieve this?
Look into Galvanic skin response sensor - It can measure electrical connectivity of the skin.
When internal or external forces cause arousal — of any kind — the skin becomes a better conductor of electricity. Essentially, when you start to sweat, either from exercise or something else, the band will be able to monitor that.
Detecting when someone is sweating gives the software more information about what a user is doing, which allows for better health tracking. Being able to correlate the level of activity with a different source than just gravity from the accelerometer, allows these programs to take on a more trainer-like role — recommending specific exercises and levels of exertion.
Hope this helps!
I'm trying to choose an API to match object images taken with a cell phone with a list of images in a file system. The point is, I'm afraid that I won't get reliable results and it won't be worth it to loose time in this feature.
I would really appreciate some advice regarding this topic.
I'm working a project which uses PHP to retrieve data from a MySOL database and is supposed to be parsed and displayed real-time as a heat-map in WP7.
Some queries return 5000+ POIs with data (latitude, longitude, values etc....). I've searched and tried implementing some examples I found but ran into some memory usage problems because of the amount of data being visualized.
My question is: What is the best way to display that quantity of data, as heat maps, efficiently on a WP7?
IMO, the best way is converting your POIs into tile images (either completely offline, or by writing a server-side code that queries your MySQL and builds the PNGs), and then overlay your tiles atop of the map. BTW, PHP is not the best tool for such tasks.
See this article: Adding Tile Overlays to the Map
I am using Bing Maps with Ajax and I have about 80,000 locations to drop pushpins into. The purpose of the feature is to allow a user to search for restaurants in Louisiana and click the pushpin to see the health inspection information.
Obviously it doesn't do much good to have 80,000 pins on the map at one time, but I am struggling to find the best solution to this problem. Another problem is that the distance between these locations is very small (All 80,000 are in Louisiana). I know I could use clustering to keep from cluttering the map, but it seems like that would still cause performance problems.
What I am currently trying to do is to simply not show any pins until a certain zoom level and then only show the pins within the current view. The way I am currently attempting to do that is by using the viewchangeend event to find the zoom level and the boundaries of the map and then querying the database (through a web service) for any points in that range.
It feels like I am going about this the wrong way. Is there a better way to manage this large amount of data? Would it be better to try to load all points initially and then have the data on hand without having to hit my web service every time the map moves. If so, how would I go about it?
I haven't been able to find answers to my questions, which usually means that I am asking the wrong questions. If anyone could help me figure out the right question it would be greatly appreciated.
Well, I've implemented a slightly different approach to this. It was just a fun exercise, but I'm displaying all my data (about 140.000 points) in Bing Maps using the HTML5 canvas.
I previously load all the data to the client. Then, I've optimized the drawing process so much that I've attached it to the "Viewchange" event (which fires all the time during the view change process).
I've blogged about this. You can check it here.
My example does not have interaction on it but could be easily done (should be a nice topic for a blog post). You would have thus to handle the events manually and search for the corresponding points yourself or, if the amount of points to draw and/or the zoom level was below some threshold, show regular pushpins.
Anyway, another option, if you're not restricted to Bing Maps, is to use the likes of Leaflet. It allows you to create a Canvas Layer which is a tile-based layer but rendered in client-side using HTML5 canvas. It opens a new range of possibilities. Check for example this map in GisCloud.
Yet another option, although more suitable to static data, is using a technique called UTFGrid. The lads that developed it can certainly explain it better than me, but it scales for as many points as you want with a fenomenal performance. It consists on having a tile layer with your info, and an accompanying json file with something like an "ascii-art" file describing the features on the tiles. Then, using a library called wax it provides complete mouse-over, mouse-click events on it, without any performance impact whatsoever.
I've also blogged about it.
I think clustering would be your best bet if you can get away with using it. You say that you tried using clustering but it still caused performance problems? I went to test it out with 80000 data points at the V7 Interactive SDK and it seems to perform fine. Test it out yourself by going to the link and change the line in the Load module - clustering tab:
TestDataGenerator.GenerateData(100,dataCallback);
to
TestDataGenerator.GenerateData(80000,dataCallback);
then hit the Run button. The performance seems acceptable to me with that many data points.
For a project we are using the Telerik RadChart control to display a graph on a website. At the moment the X-axis follows a normal scale but we would like to change that to a logarithmic scale. As far as we can tell the control does not allow that.
Does anyone know of an alternative that would support this?
TIA,
David
Example of what we would like to achieve.
"Unfortunately the current version of RadChart does not support logarithmic X-Axis. We have already logged such a request in our public issue tracking system, you can find it here, however, taking a decision for implementing a certain feature depends on multiple conditions including complexity, existing features impact, demand rate, etc. It is not yet in our immediate plans, still, I would encourage you to use the above link to vote and track the issue."
Regards,
Nikolay
the Telerik team
Taken from here, as it was posted this month.