codigo

Multi-variable linear regression

I continue working with machine learning algorithms. In a previous post I talked about linear regression with one variable and I described different algorithms to predict hypothesis.

In this case, I'm playing with linear regression but, with some features. Linear regression only have one input feature and one output feature. For example, you can predict the price of a house give the house's size. But imagine that you want predict the price of a house using size and rooms features. When you have more than one input feature is called 'multi-variable linear regression'.

In the following figure we can see the two input features (size and rooms), the training data (red dots), and the predictions (blue dots). In this case, we can represent the information with a 3D model. If your model have more than three features you must research the way to represent all the data.

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By rocapal, ago
floss

Playing with machine learning: Linear Regression

Since two months ago I'm researching about machine learning and its algorithms. The goal is get a good unsupervised and clustering algorithm to analyze every android applications and predict what application you want to install or use in a particular time. The first step is learn and understand the theory of machine learning. For this,  I began to study the Machine Learning Course of Stanford. It's a great and practical course with videos and material to help understand the classes.

The first model that I have studied is linear regression. This model consist in have a relation between two or more variables. For example, in my example I have a training data about the prices of the houses and its size in square meters. This training data is used to build a linear regression model to predict the prices of the house give the size of the house. As you  can see in the following figure, the black dots show the training data (I did web crawling to get real data). The blue line represents the trend line of the model, and the red dots show the predicts for two size of houses.

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By rocapal, ago
Uncategorized

How decompile an Android Application

Decompile is a process to revert the compile operation. I main, decompile converts the low level code in high level code. The Android application is compiled in APK container that groups files as: xml, images and class. APK containers are actually ZIP containers. An interest thing is can see the xml configuration or some source code of others applications. If this applications are Free Software is not a problem, but if this applications are privated we can't see its configuration. The next application help you to decompile an APK file to see xml configuration and source code.

Some tools I've found:

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By rocapal, ago
android

The first prototype video of ESTUFA

ESTUFA is a framework that provides several ways to connect and re-use mobile applications (in previous post I already presented this idea). The system allow build “execution chains” to connect and plumb two applications. This project is based in the idea of re-use and compose new applications using components (in this Read more…

By rocapal, ago
android

Arduino & Android & ADK

The last Google I/O a new feature based in Android and Arduino was released. The ADK allows the communication between Android and Arduino using a USB connection. Google have developed a library called “USB Accessory” in Android and Arduino. So, this library help us to send and receive data through USB interface. Using Read more…

By rocapal, ago
android

New challenges about Android, AR and Arduino

During the next months I will work in three interesting topics. The first of them is the creation of a new architecture based in Android that allow communicate and integrate applications. The second  is the port of ARviewer to iPhone platform using phoneGap. And the last one is the very well-know Arduino and Read more…

By rocapal, ago
android

Distributed Video Surveillance System based on Android

Security and Surveillance Systems have always been demand in the industrial and home environment. The cameras, which human eyes are able to collect all visual information from the environment. Extensions necessary and highly desirable in these systems, and that few possess, are integration and interconnection with other systems, video surveillance and display all the information on a Read more…

By rocapal, ago
Uncategorized

ARviewer, PhoneGap and Android

Three months ago I wrote a post describing the plan that Raúl Roman and I are involved: build an augmented reality interface using PhoneGap. Today, we have uploaded a beta version (0.1.0) of ARviewer-PhoneGap to Android Market. This version works fine and shows the geolocated nodes obtained from libregeosocial server. Read more…

By rocapal, ago
android

Kinect’s depth map on your Android device

Two weeks ago, I have received the new fashion gadget of Microsoft: the kinect sensor. Thanks for the community (libfreenect), this sensor designed for Xbox can be used in GNU/Linux systems. Lately I have the need of integrate anything with Android mobile (is it because I have over 3 years programming with Android?) Read more…

By rocapal, ago
android

AR interface in Android using phoneGap

Since 6 months ago we have evaluated the possibility to implement a new AR interface (based in our project ARviewer) using phoneGap. phoneGap is a mobile framework based in HTML5/JS that allow execute the same source code HTML5 in differents mobile platforms (iphone, android, blackberry). It seem a good way Read more…

By rocapal, ago