My favourite mountain place, Castell'Azzara, in New Year first morning Posted by Hello

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Docker for our ROS robotic overlords

The typical robotic stack is based on the Robotic Operating System (ROS) whose version is linked to a specific Ubuntu LTS distribution, e.g. Indigo-14.04 and Kinetic-16.04 to mention the most recent ones. When working with recent laptops it is possibly that even with a kernel update (like Linux 4.4) it is not possible to have a good working machine.

This post aims at providing some basic indications for using the Docker container system for creating a ROS setup with a different Linux distribution together with GPU support, e.g. running ROS Indigo inside Ubuntu 16.04. Docker is used in the industry for isolation and easy deployment, and in this case it solves the compatibility problem with minimal performance penalty.

We are using this approach internally at PERCRO laboratory of SSSA for working with research robots developed in RAMCIP and ReMeDi, and also with the Baxter robot from Rethink Robotics. The post provides a basic recap also on Docker for the minimal elements useful for pu…
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cmakego: Simpler access to external libraries in CMake

CMake has greatly simplified the process of building libraries and applications across different platforms, and it is adopted by several large projects. Libraries can be easily found through find_package but the result of the lookup has to be manually added to the target through different commands. This post discusses how include the external libraries in an easier way:

add_executable(glapp1 glapp1.cpp ...)
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Details after the break.

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Algebrical Data Types in C++

Update: next post is here

The subtitle of this post could be C++11 is cool, but let's start from the beginning.

The starting point is the long standing argument on reporting error states of functions by means of exceptions or by multivalued functions. Recent languages such as Go by Google and Swift by Apple prefer to manage error states in the second form, while C++ and Java are biased toward exceptions (See [6] for a discussion). 

Multivalued functions are based on the concept of sum-types, also called algebrical types in other languages such as Haskell, or tagged unions. A sum-type is defined by a list of types, and a sum-type variable contains a typed value from such a list. A sum-type is similar to unions, except that the current type of the union is managed automatically; also a sum-type can be considered complementary to C++11 tuples. In particular we can say:
multi-type, single-value: sum-type/variant multi-type, multi-value:  tuplesingle-type, multi-value: vector or array …
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