I have a dataset of ~300 electoral districts (~10MB - 45MB depending on the file format - GML/KML/SHAPE/JSON). I'm hoping to build a mobile app (iOS/Android/Windows Phone) that will determine which electoral district a user is in based on their current lat/lon.
My original plan was to set up an Azure webservice and use SQL Server or DocumentDB's spatial functionality to provide the answer. But the electoral districts are fairly static, so if I can do this on the device it might be better.
I'm thinking I'll likely use Xamarin.Forms to build my app since the UI doesn't need to be that complex (I don't need to draw maps or electoral districts).
I see that EF6 seems to have spatial functionality that would work, but I'm finding conflicting info about whether or not that will work with Xamarin.Forms, or if the performance will be reasonable.
What's the best (fastest/simplest) library/class I can use to determine the electoral district locally in a Xamarin.Forms app?
I wasn't able to find a library/class, but it seems like I can code a solution myself with little effort. I found this link: http://www.codeproject.com/Tips/84226/Is-a-Point-inside-a-Polygon . I didn't quite understand it the first time I looked at it, but now it makes sense.
My plan is to store my electoral district (polygons) in SQLite locally. But, I'll also include 4 columns for min/max lat/lon of each polygon. That gives me the minimum bounding rectangle for each polygon, and will serve as a primitive spatial index of sorts to quickly identify a small subset of possible electoral districts. From there I can use the algorithm found on CodeProject to confirm which electoral district is the correct one.
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I am in a bit of a crisis here. I would really appreciate your help on the matter.
My Final Year Project is a "Location Based Product Recommendation Service". Now, due to some communication gap, we got stuck with an extremely difficult algorithm. Here is how it went:
We had done some research about recommendation systems prior to the project defense. We knew there were two approaches, "Collaborative Filtering" and "Content Based Recommendation". We had planned on using whichever technique gave us the best results. So, in essence, we were more focused on the end product than the actual process. The HOD asked us what algorithms OUR product would use? But, my group members thought that he meant what are the algorithms that are used for "Content Based Recommendations". They answered with "Rule Mining, Classification and Clustering". He was astonished that we planned on using all these algorithms for our project. He told us that he would accept our project proposal if we use his algorithm in our project. He gave us his research paper, without any other resources such as data, simulations, samples, etc. The algorithm is named "Context Based Positive and Negative Spatio-Temporal Association Rule Mining" In the paper, this algorithm was used to recommend sites for hydrocarbon taps and mining with extremely accurate results. Now here are a few issues I face:
I am not sure how or IF this algorithm fits in our project scenario
I cannot find spatio-temporal data, MarketBaskets, documentation or indeed any helpful resource
I tried asking the HOD for the data he used for the paper, as a reference. He was unable to provide the data to me
I tried coding the algorithm myself, in an incremental fashion, but found I was completely out of my depth. I divided the algo in 3 phases. Positive Spatio-Temporal Association Rule Mining, Negative Spatio-Temporal Association Rule Mining and Context Based Adjustments. Alas! The code I write is not mature enough. I couldn't even generate frequent itemsets properly. I understand the theory quite well, but I am not able to translate it into efficient code.
When the algorithm has been coded, I need to develop a web service. We also need a client website to access the web service. But with the code not even 10% done, I really am panicking. The project submission is in a fortnight.
Our supervisor is an expert in Artificial Intelligence, but he cannot guide us in the algorithm development. He dictates the importance of reuse and utilizing open-source resources. But, I am unable to find anything of actual use.
My group members are waiting on me to deliver the algorithm, so they can deploy it as a web service. There are other adjustments than need to be done, but with the algorithm not available, there is nothing we can do.
I have found a data set of Market Baskets. It's a simple excel file, with about 9000 transactions. There is not spatial or temporal data in it and I fear adding artificial data would compromise the integrity of the data.
I would appreciate if somebody could guide me. I guess the best approach would be to use an open-source API to partially implement the algorithm and then build the service and client application. We need to demonstrate something on 17th of June. I am really looking forward to your help, guidance and constructive criticism. Some solutions that I have considered are:
Use "User Clustering" as a "Collaborate Filtering" technique. Then
recommend the products from similar users via an alternative "Rule
Mining" algorithm. I need all these algorithms to be openly available
either as source code or an API, if I have any chance of making this
project on time.
Drop the algorithm altogether and make a project that actually works
as we intended, using available resources. I am 60% certain that we
would fail or marked extremely low.
Pay a software house to develop the algorithm for us and then
over-fit it into our project. I am not inclined to do this because it
would be unethical to do this.
As you can clearly see, my situation is quite dire. I really do need extensive help and guidance if I am to complete this project properly, in time. The project needs to be completely deployed and operational. I really am in a loop here
"Collaborative Filtering", "Content Based Recommendation", "Rule Mining, Classification and Clustering"
None of these are algorithms. They are tasks or subtasks, for each of which several algorithms exist.
I think you had a bad start already by not really knowing well enough what you proposed... but granted, the advice from your advisor was also not at all helpful.
We use a solution in C#.net where someone can call a phone number and speak a persons First, and then Last Name. Then the name is entered on a guest registry on our website. We use an XML dictionary file with 5,000 First Names and 89,000 last names that we got from the US Census. We are using the Microsoft.Speech.Recognition library, (maybe that's the problem).
Our problem is that even with relatively easy names like Joshua McDaniels we are getting about a 30% fail rate. The performance, (speed-wise), is fine it just doesn't grab a good portion of the names.
Now, I understand that ultimately the quality of the spoken name will dictate, sorry for the pun, how well the system performs, but what we would like to get close to 99% in "laboratory" conditions with perfect enunciation and no accent and then call it good. But even after several trials with the same person speaking, same name, same phone, same environment, we are getting a 25% fail rate.
My question is: Does anyone have an idea of a better way to go after this? We thought of maybe trying to use an API, that way the matches would be more relevant and current.
The current state of the technology is that it is very hard to recognize names, moreover a large list of them. You can recognize names from the phone book (500 entries) with good quality, but for thousands of them it is very hard. Speech recognition engines are certainly not designed for that, in particular offline ones like System.Speech.
You might get way better results with online systems like https://www.projectoxford.ai which use advanced DNN acoustic models and bigger vocabularies.
There were whole big companies built around the capability to recognize large name lists, for example Novauris
used patented technology for that. You might consider building something like that using open source engine, but it would be a large undertaking anyway.
I am working on an ASP.NET project that is relatively simple except for one requirement which requires custom questionnaires be attached to specific types of tasks. These questionnaires need to be customized regularly and no development, within the app itself, should be needed add questionnaires. The questionnaires currently do not require an editing tool and can be done by uploading a template, changing something in a DB, whatever. They can be stored in any format and the resulting output needs to be captured to be edited or viewed later.
The types of questions in the questionnaire could be:
Selections (select one from a list)
Input (text, integers, dates, etc)
Yes/No
The ability to display questions based on answers from other questions. For example if they answer yes to question X, display question Y else display question Z. Need to be able to apply data validation such as required fields, ranges, etc on questions (could all be probably capture by basic regex).
The simplest break down would be:
Create a new event.
Based on the type of event display a specific questionnaire.
Questionnaires can change over time but they can be considered as new version each time and data will always be related to a specific version and not need to be migrated to updated versions.
The questionnaire output (data elements and a final calculated value) must be captured.
XML output (or any other format) of data elements entered.
The optimal (unicorn) scenario would be to have a basic template in XML or something that a user can learn to create easily and it would be stored and versioned in a DB. When a user makes a new event, the app would fetch the appropriate template which would display the questionnaire to the user. The user would fill it out and the output would be posted as some type of output (again XML would be nice but not required). That output would be attached to the event. Done.
Are there any .NET compatible tools/libraries that I could leverage to accomplish this? InfoPath seems like a tool that might be of use but I have almost zero experience with it so I am not sure about its constraints / implementation and if it is just overkill. The solution needs to be contained within the ASP.NET application. An external editor tool for creating templates would be ok but the templates must be viewable and editable on the web with no constraints to the user.
Can anyone provide examples of this being done or hints on how you might have tackled this?
Since the application is relatively easy to create other than this one feature, I would rather not spend 80% of my time trying to implement the custom questionnaire functionality and spend more time on the problem the application is trying to solve.
Tech available: ASP.NET, Silverlight, SQL Server
I would suggest having a look at a dot net nuke implementation, I am sure there should be a lot of viable options (if not all free).
DotNetNuke
Have a look at the Forge to see free plugins
Consider evaluating SurveyMaster at CodePlex. It's licensed under Microsoft Public License (Ms-PL), and you can modify its source for your needs.
I need to find if the given zip code is within the required radius. For example, if the user has entered 20910, it should be able to determine if it's within 5 mile radius of 20814. Is there a way to do it? Google API or something? Please help.
I'm using C# as the programming language.
Thanks.
You are going to need some source of geodata. Here is an older source that you can download. link . Or you may try Live Local or Google Api services
I don't know Google API support this things, but you can choice off-line solution too; you need for it some database with zipcodes and some LATITUDE/LONGITUDE range for each. Then you can with simple calculations get result what you want.
Pros of off-line choice:
Don't need network connection
Database must exists and must be up-to-date (but this is not often changes, zipcodes)
You are not addicted to Google API.
Cons of off-line choice:
You must write algorithm who determinate by point and area, is this point is in 5mile radius from area, i don't know on what level is your programming experience, for me is easy, for you i dont know, think about you can write it.
What libraries are there to write C# internationalized applications?
Typical functionalities that should be contained in the library:
Validation of country specific data (e.g. VAT numbers, phone numbers, addresses,...)
Validation of bank and financial coordinates (e.g. Credit Card numbers, IBAN,...)
Language-specific functionalities (e.g. numbers to words to numbers, summarize,...)
Language specific content filtering (e.g. swearword filtering...)
An example of such libraries in Perl would be the Internationalization/Locale section of CPAN.
What C# solutions are available?
Note: I am not looking for an introduction to the System.Globalization namespace :)
Note 2: Should I desume that there are no options available? Is someone interested in joining forces and create one?
Note 3: Edit to make the question appear on front page in hope of more answers. This isn't such a hard question, how is it possible that Stackers don't ever do i18n?
One project that is working towards a database of globalization, internationalization and localization knowledge is the Unicode Common Locale Data Repository, based on the old ICU project at IBM.
As it is a database of XML data it doesn't contain any .NET-specific code, but as a body of knowledge it is very good.
Only a smallish subset is in the .NET framework. Microsoft hasn't gone near any of the supplemental stuff, like postcode formats, number spelling (for check/cheque amounts), etc. Standard time zone names (from the Olson/tz distribution), etc. are also included, with mappings to the Windows-specific names. Some of the hierarchical locale-specific behaviours also have better support.
I wouldn't say that no one does i18n, but I don't know of any generic tools that can be used for every project. Maintaining a database with all of the information you are looking for would be an epic project. It sounds like what you're looking for isn't a specific C# library, but more a collection of information online that you can draw from. If you were able to find a repository of swear words in various languages (for example), it would be trivial for you to use this in C#. I think that finding a solution that wraps up all of your requirements into an easy-to-use assembly is going to be impossible to find.
Have a look at
http://www.microsoft.com/globaldev/getwr/dotneti18n.mspx
and
http://www.dotneti18n.com/
String to number and vice versa can be dones as following:
culture = new CultureInfo(locale);
int number = Convert.ToInt32(myString, culture.NumberFormat);
string str= Convert.ToString(myNumber, culture.NumberFormat);
As to checking VATS and adresses, I'm interested in that too, haven't found anything useful so far.
Not exactly a "library", per se, but I've actually ran into a great service (for pay), by a company called E4X (former client of mine).
What they provide is complete localization of your ecommerce site, including language translations, currency exchanges, local billing and handling of financial transactions including region-specific taxes etc, and more. They even deal with logisitics of physical shipping...
Worth looking into, for an ecommerce business. Let 'em know I sent you... ;-)
That's a huge endeavor. Let's start with one simple problem: phone numbers. Libphonenumber Google library at http://code.google.com/p/libphonenumber/ has a C# port at https://bitbucket.org/pmezard/libphonenumber-csharp with notes at http://blog.thekieners.com/2011/06/06/using-googles-libphonenumber-in-microsoft-net-with-c/. Appears to be a good library for handling both US and int'l numbers.