I'm thinking of building an application that helps you find local businesses (just an example). You might enter your zip code (or GPS if this is on a phone) and find the closest business within 10 miles, etc. My question is how can I achieve this type of logic? Is there a library or service that I will need to use? Or can this be done with math? I'm not familiar with how this sort of thing usually works, so let me know how I need to store the records so I can query them later. Note: I will be using Ruby and MongoDB.
It should be easy to find the math to solve that, providing lat/long coordinates.
Or you could use some full featured gem to do that for you like Geocoder, that supports Mongoid or MongoMapper.
Next time you need some feature that might be a commun world problem, first check if there is a gem for that at ruby-toolbox, for this case here are some other gems for geocoding
One more solution here...
http://geokit.rubyforge.org/
I think, this topic is already discussed here..
Related
I have users that have authenticated with a social media site. Now based on their last X (let's say 200) posts, I want to map how much that content matches up with a finite list of keywords.
What would be the best way to do this to capture associated words/concepts (maybe that's too difficult) or just get a score of how much, say, my tweet history maps to 'Walrus' or 'banana'?
Would a naive Bayes work here to separate into 'matches' and 'no match'?
In Python I would say NLTK can easily do it. In Ruby maybe gem called lda-ruby will help you. Whole LDA concept is well explained here - look at Sarah Palin's email for example. There's even the example of an app (not entirely in Ruby, but still) which did that -> github.com/echen/sarah-palin-lda
Or maybe I just say stupid things and that can't help you at all. I'm not an expert ;)
A simple bayes would work in this case, it is highly used to detect if emails are spam or not so for a simple keyword matching it should work pretty well.
For this problem you could also apply a recommendation system where you look for the top recommended keyword for a user (or for a post).
There are a ton of ways for doing this. I would recommend you to read Programming Collective Intelligence. It is explained using python but since you know ruby there should be not problem to understand the code.
Is there a way to understand what an image is about? I mean, if I scann a picture, how can I tell that the picture is about a spesific object? I am thinking that if I have some shape in mind, say the shape - pattern of a spesific object that meets its requirements against the object I am searhcing for, then it must be what I am looking for. Anyway I am thinking of an algorithm to scann a picture database and figure out the pictures I am actually looking for,Is there a known way to accomplish such operation?.
If I am reading your question correctly...
This is a very daunting task even for full-fledged corporations like Google, though they are attempting to create something along these lines.
Take a look at Google Goggles for Android if you'd like to see how this sort of system behaves. You'll also notice that it requires very specific circumstances to be even slightly reliable, but the base technology is there.
I'm building a site that allows users to make sense of a debate by graphically representing arguments for and against a particular issue. (Wrangl)
I'd like to categorise these debates so they are more easily found and connected. I don't want to irritate the person creating the debate by asking them to add tags and categories before they see any benefit, so I'm looking at a way of automatically extracting keywords.
What's a good approach for taking the debate's title and description (and possibly the content of the arguments themselves once there are some) to pull out, say, ten strong keywords that could be used as metadata to connect similar debates together, or even as the content of the "meta" keywords tag in the head of the HTML page where the debate is viewable. Eg. Datamapper vs ActiveRecord
The site is coded in Ruby with Sinatra, using DataMapper for data storage. I'm ideally looking for something which will work on Heroku (I don't have a way of writing files to disk dynamically), and I'd consider a web service, an API or ideally a Ruby gem.
Maybe you can use TextAnalyzer.
I understand that you're wanting to find an easy way of achieving this, I've recently dived into the world of NLP (Natural Language Processing) and Text-mining and its a daunting process of which most went far above my head.
Although i managed to code some functionality that resembles what you're looking for, though I did it in PHP. What i would suggest, that if you want it tailored to your project (Wrangl) then do it yourself.
Using the Porter stemming algorithm which I'm sure there will be Ruby code for.
Ruby Porter stemmer
You can try the salsaAPI to automatically extract keywords and categorize the debates!
I'm looking for a library or technique to detect the input language of blocks of text provided by users. Online lookups (like Google translate) won't work for this task as I'm writing an app which must run offline.
Thanks.
Here are two more n-gram-based gems you might want to try. They work offline.
https://github.com/echen/unsupervised-language-identification, optimized for separating english and other languages (has a live demo)
https://github.com/feedbackmine/language_detector, less specialized, will detect more languages. Some languages may need some extra training — I found it to be not precise enough for German text.
For anyone interested, I've found http://rubygems.org/gems/kenwaln-whatlanguage, which is performing excellently.
I'm using CLD which I really like, succinct and easy to use. Give it a try.
A quick demo of WhatLanguage in Ruby:
http://www.youtube.com/watch?v=lNqZ2cqOReo&list=UUJ_3fstMOH-g4yBxtvgAWkw&index=0&feature=plcp
I have a list of airport names and my users have the possibility to enter one airport name to select it for futher processing.
How would you handle misspelled names and present a list of suggestions?
Look up Levenshtein distances to match a correct name against a given user input.
http://norvig.com/spell-correct.html
does something like levenshtein but, because he doesnt go all the way, its more efficient
Employ spell check in your code. The list of words should contain only correct spellings of airports.
This is not a great way to do this. You should either go for a control that provides auto complete option or a drop down as someone else suggested.
Use AJAX if your technology supports.
I know its not what you asked, but if this is an application where getting the right airport is important (e.g. booking tickets) then you might want to have a confirmation stage to make sure you have the right one. There have been cases of people getting tickets for the wrong Sydney, for instance.
It may be better to let the user select from the list of airport names instead of letting them type in their own. No mistakes can be made that way.
While it won't help right away, you could keep track of typos, and see which name they finally enter when a correct name is entered. That way you can track most common typos, and offer the best options.
Adding to Kevin's suggestion, it might be a best of both worlds if you use an input box with javascript autocomplete. such as jquery autocomplete
edit: danish beat me :(
There may be an existing spell-check library you can use. The code to do this sort of thing well is non-trivial. If you do want to write this yourself, you might want to look at dictionary trie's.
One method that may work is to just generate a huge list of possible error words and their corrections (here's an implementation in Python), which you could cache for greater performance.