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Anaconda and ROS in Ubuntu 16.04 setup mistake

Anaconda and ROS in Ubuntu 16.04 setup mistake

I made a small mistake in my setup of Anaconda I believe that effected my install of ROS packages and effected using roslaunch.

I wanted to make a small blog post for my reference and anyone who happens to stumble upon it.

Basically when you edit your .bashrc you can set the PATH variable incorrectly.

Below is the variable as it should be, obviously you have to change the path to be your username.  If you put your path to the anaconda bin behind the $PATH variable appending it will cause your anaconda python version to be searched in first.  This is probably obvious to some, but I made the mistake.

export PATH=”$PATH:/home/username/anaconda3/bin”

 

If you made your install it is also useful to make sure your ROS install is also using Python 2 and not Python 3.  Also the reason “python” should be referred to as python 2 is because in the python documentation they tell developers to always refer to python as python 2 in the future and anything using python 3 should be referred to as python3 to avoid issues.

If for some reason you want to circumvent this you can install alternatives in Linux.

update-alternatives –install /usr/bin/python python /usr/bin/python2 1

update-alternatives –install /usr/bin/python python /usr/bin/python3 2

 

That adds those python binaries to the system for alternatives lists.  After you add them you can then set a default and easily alternate as well.  If you wish to assign it is easy.  I will also add this works for many different things on the system.

update-alternatives –config python

Stop Hurricanes

Stop Hurricanes

After reading this older article while searching for current methods to stop a hurricane I was kind of let down by the fact it seems most current valid methods to stop a hurricane aren’t being attempted. We have already had 4 hurricanes within the last month and no one is even trying anything.

The article I am referring to – http://www.popsci.com/science/article/2012-11/why-can’t-we-stop-hurricane-it-hits-us#page-3

Saying we shouldn’t stop a hurricane because of unintended consequences seems irrational given we move water across the globe along with many gases, trash, etc.. with little regard. At least trying to stop a hurricane seems a worthy effort given the cost of attempting to stop something and succeeding would cost less then the damage it produces. If we eventually want to terraform other planets we should figure out how to control Earth.

If you aren’t familiar with the process of terraforming you can look here – https://en.wikipedia.org/wiki/Terraforming.

The process will never be understood if we can’t understand our own Earth processes. We need accurate models and readings from our Earth’s surface, oceans, airways and interior. Once we collect data we can do what many meteorologists already do. They create models or movement. I think employing artificial intelligence to this area will greatly improve the speed of our mastery in this area.

associate ssh key with git remote host

associate ssh key with git remote host

I often run into to issues where I like to use different ssh keys for different sites, servers, and other things.  It is a good practice not to use the same key for everything just in case you need to change it, or other various reasons.  If you are like me and don’t want to manually enter the path to theses keys each time you can associate them with a url.  So if you were connecting via ssh, or over git with ssh it works perfectly.

So first generate a key.  In this example we will create one for Bit Bucket.

ssh-keygen -f ~/.ssh/bitbucket

Now inside the ~/.ssh folder edit the config file and add the text below.

Host bitbucket.org
IdentityFile ~/.ssh/bitbucket
IdentitiesOnly yes

At this point when you push to bitbucket it will use this key.. For example if you added the remote repo as origin

git push origin master

It should prompt you for your ssh unlock pass phrase.

Cooking Vegan and Wolf Dog

Cooking Vegan and Wolf Dog

Hey just wanted to show you guys my wolf dog and an easy Vegan pizza recipe that tastes really good.

The ingredients are your standard dough low in oils of course.  No milk, eggs, or any animal products of course and then basically beans, lentils, cashews, and tomato sauce.   It is really a simple recipe and quick to make.

Any way have a look.

Something funny & something useful

Something funny & something useful

I was working on something and I noticed something really funny in the Qt documentation.  Have a look….   qscrollarea-onescrollbaror go to http://doc.qt.io/qt-5/qscrollarea.html  If this isn’t prime material for a programmers meme I don’t know what is.  I have no idea why they inserted this picture as the example other then to have a good time with the material they decided/or had to write.  Very funny either way.  Thanks for the unexpected laugh Qt document writers.  I was reading the documentation because I needed to create my own version of a photo editing area.  I even posted an adapted example on stackoverflow here : http://stackoverflow.com/a/28147336/1325621

If it is not completely obvious this little snippet helps you align your QImage inside a widget.

This isn’t the final version, but it definitely gives some one a good starting point.  If anyone is interested in an updated version with more features let me know.