How to clean up PackageKit in Fedora OS the right way !

Question
Is there a proper way to clean up old PackageKit caches without resorting to low level sudo rm -rf /var/cache/PackageKit/2[3-4] etc.

 

Answer

The man pkcon, and  PackageKit does not seem to provide a command to clear the cache.

The best method is to tell PackageKit not to cache that is store packages at all. This can be achieved here

/etc/PackageKit/PackageKit.conf: uncomment #KeepCache=false (to make it look like: KeepCache=false)

And if you use dnf to update, you tell PackageKit not to download any updates automatically:

gsettings set org.gnome.software download-updates false

Also in Fedora 26 and above,

I found that pkcon refresh force cleared out PackageKit-cached RPMs that were from currently-enabled repositories and had already been installed elsewhere, that is via DNF !

Geeky way to add more workspaces in Lubuntu !

Well Lubuntu is a solid and most used Ubuntu derivative which is extremely lightweight and can become a solid choice for the users who use a older harware, say a 8 to 10 year old computer.

Here on any given Lubuntu machine the default workspaces are 2. But to increase it we can become a root and fire the given command below :-

wmctrl -n 5

This means, make 5 desktops. Read man page for more info. It is quite useful program.

Or the other way is

Fire the terminal, that is (hit on Alt-F2) and enter “obconf” (without quotations). Click on “Desktops” and choose the number of desktops that you want. In addition, by double clicking Desktops name, you can rename Desktops as desired.

Or

Add a ppa,

First, we’ve got to add a line to our /etc/apt/sources.list file.

ppa:geod/ppa-geod

then

sudo apt-get install indicator-workspaces
sudo apt-get update
sudo apt-get upgrade

Start managing workspaces from indicator-workspaces.

 

Voila now you’re done !

 

Install R and Rstudio in Ubuntu 16.04 LTS !

R is a programming language and free software environment for statistical computing and graphics that is supported by the R Foundation for Statistical Computing. The R language is widely used among statisticians and data miners for developing statistical software and data analysis.
R is hot. Whether measured by more than 10,000 add-on packages, the 95,000+ members of LinkedIn’s R group or the more than 400 R Meetup groups currently in existence, there can be little doubt that interest in the R statistics language, especially for data analysis, is soaring.

Why R? It’s free, open source, powerful and highly extensible. “You have a lot of prepackaged stuff that’s already available, so you’re standing on the shoulders of giants,” Google’s chief economist told The New York Times back in 2009.

Note:- You can find the R-Base in the Ubuntu Software Center, but mostly they can be outdated. Now to make sure that you are on the most updated package repository, we need to add a repo. First, we’ve got to add a line to our /etc/apt/sources.list file.

Note the “xenial” in the line, indicates that it’s Ubuntu 16.04. If you have a different flavour or versions of it, just change that respectively.

sudo echo "deb http://cran.rstudio.com/bin/linux/ubuntu xenial/" | sudo tee -a /etc/apt/sources.list

Add the Keyring.

Firstly,

gpg --keyserver keyserver.ubuntu.com --recv-key E084DAB9

Then,

gpg -a --export E084DAB9 | sudo apt-key add -

Install the R-Base

sudo apt-get update
sudo apt-get install r-base r-base-dev

Install the R Studio

sudo apt-get install gdebi-core
wget https://download1.rstudio.org/rstudio-1.0.143-amd64.deb
sudo gdebi -n rstudio-1.0.143-amd64.deb
rm rstudio-1.0.143-amd64.deb

That’s it.

Note:- In case you get stuck while executing the above commands one by one just run, this:-

CTRL+C to stop then

sudo apt-get clean

to clean your local repo and then try the command again

sudo apt-get install r-base r-base-dev

Image courtesy:-

askubuntu

wikipedia

computerworld

5G – The future and beyond, for the upcoming decade !

Dubbed as “Fifth Generation” or simply referred to as 5G. This upcoming technology beholds and unleashes a promising future for all the connected people(via World Wide Web) on the planet. At last year’s CES 2017(Consumer Electronics Show), Qualcomm CEO, Steve Mollenkopf described “5G” as the biggest thing since the introduction of electricity. In short you would have a better access to the internet, of course blazing fast speeds without any bottlenecks are some of the the key areas and this supersedes 4G as of now as a the current technology. The real advantages, however, boil down to these things:

Reliability: 5G doesn’t just deliver peak speeds in ideal conditions. The technology offers superhigh speeds that are reliable and consistent, even indoors or in congested areas.

Bandwidth: 5G can support a massive increase in connected devices. Ericsson forecasts 1 billion 5G subscriptions by 2023. Think sensors on everything.

Latency: Phones today have an annoying lag between when you send a request for a website or video and when the network responds. With 5G, that’ll be reduced to 1 millisecond. That’s 400 times faster than the blink of an eye.

VR & Entertainment:-

The millisecond ping time which is crucial and is also central to creating hyperreal virtual and augmented reality experiences. Haptic VR, which lets users touch and feel what they’re seeing in their virtual surroundings, relies on 5G’s low latency to detect where a user is in the virtual space. It then provides physical feedback in close to real time. The statements below are from Intel’s former head of Iot & connected devices networks. In few years there may be a device for viewing and experiencing live sports for example a basketball match where the wearable VR does the magic on a 4k streaming content viewed in a 360 degree wide angle.

The next wave of gadgets will all be connected on a “completely transformed network,”. The connectivity will be seamless, invisible and instant. No buffering, no lag, no clogged network.

“Kind of like magic behind the curtain,”

Self-driving cars or driver-less cars:-

This can be the same case as that of drones which can be used for carrying and shipping your next pizza order to Amazon delivering at your court-yard. For every smart city there is a requirement of smart cars or driver-less cars. Ford, Audi, Mercedes-Benz, Hyundai, etc are already in the picture and are gearing up to make the dream come true.

Here you need not drive your car, just be seated and let the technology do the uplifting. Set location and the rest is taken care automatically like the traffic, best route, speed limits, traffic signals etc. It’s connectivity at it’s best. You could also become more productive by doing your work by sitting inside. Google is also doing this and we may see them in next few years.

 

Smart Homes:-

This category comes under IoT, consider a automatic juicer or a toaster, a ceiling fan or a microwave say all of them are connected together via internet and could probably be accessed by your smartphone. The smart house also consist of automatic door bells, proximity sensors, bio-metrics,  closed circuit tv’s etc. Intel’s Asha Keddy has some thoughts:-

 “We’re not just going to be connecting 6 or 7 billion people, we’ll be connecting tens of billions of things,” said Keddy. “It will be phones, lights, cars, buildings, appliances, you name it.”

Remember, a lot of work needs to be done for 5G to achieve mainstream recognition. But with networks set to go live by 2019 and coverage reaching 20 percent of the population by 2023, now’s the time to start caring about it.

[via:- cnet news]

Format USB stick in Ubuntu or any other Linux distro using command line !

Howdy folks.

Formatting or factory reset/format or erase all the content of the external drive is pretty easy when done via GUI tools such as Gparted or Disks in Linux. But what if there are errors shown while formatting etc. We need to hard reset the flash drive anyhow to make it fresh and clean for maybe a new installation of the OS via burning the ISO on to the flash drive or for some other nerdy quests. Now here is the way of doing this via CLI on any Linux distro possible out there.

  • First, you have to find out which device (/dev/sd??) your USB stick is. Become a root user first type
    sudo -i
    fdisk -l
    
  • After that unmount the device/partition (if necessary) by running
    sudo umount /dev/sd**
    

    Make sure you replaced ** (asterisk)with the correct device/partition name from the above output.

  • To format The partition as FAT32 use
    sudo mkdosfs -F 32 -I /dev/sd**
    

    Again replace ** with your respective letters.

Be extremely careful that if you enter the wrong device name, you might also accidentally format your hard disk!

You may also type the below incase you don’t wanna be a root user throughout the process

    sudo -s

[via:- askubuntu forums]

Is Java a bad introductory programming language ? says many Universities !

We are all aware of Java, the high level programming language King, taught at almost all the universities in the world, including the students pursuing their Computer Science degree at Graduation level. But what’s really new and staggering is that the Stanford University has recognised that it’s extremely clunky and syntactically bloated. Specially for those, the one’s coming from a new learning curve(newbies).

The course CS 106A is the old Java now, as per the revised syllabus and the new  formerly introduced one is JavaScript course CS 106J. You can watch them on YouTube too if you want to learn.

The decision to ditch Java has it’s caveats at one end. While there’s a lot to like about it, Java is perhaps the harshest language you can learn as a new comer. In fact, in this respect, it’s straight-up awful and perhaps boring too.

Let’s just take a look at perhaps the first Java program you’ll write, My World

class My World {
public static void main(String[] args) {
System.out.println("My World!");
}
}

Put yourselves in the shoes someone learning to code for the very first time. There’s a lot of scary things down here.

Now, let’s compare that to the JavaScript guys !

alert('My World!');

It’s a lot more digestible, isn’t it? Just by looking it, you can figure out what it does, even if you’ve never written a line of code in your entire life.

You are not immediately burdened with that, things like static typing, functions, and object oriented programming etc.

Now see the graph in my featured image where you just clicked to read this article, almost 60 percent of institutions surveyed reported using Java as an introductory language. C++ followed it, with nearly 10 % of institutions using it. Only 3 % of institutions used Python so far, which is hot and happening these days specially for developer arena.

Other languages that made the list include MATLAB, C and C++, Scheme, Scratch, and of course Java.

Too much sad to say, bad ideas often die hard, isn’t it !

 

LibreOffice dubbed MUFFIN a “Ribbon” typed interface(optional) is coming !

The popular open source software suite from the Document Foundation is going to make a relative stride forward by introducing the so called Ribbon UI which resembles any Microsoft Office software in the modern era. The package comes as an entire optional thing and gives the end user the freedom of which interface to be choose from. Here are some of them below:-

  1. Notebook bar (dubbed as Ribbon UI)
  2. Single Toolbar
  3. Single Toolbar plus Sidebar
  4. Classic Toolbar.

What is MUFFIN?

All 4 of the new layouts are part of the tasty acronym called MUFFIN. MUFFIN stands for “My User Friendly & Flexible INterface”.

The question is that the Open source software suite wants to classify the users, in terms of their genre from age limits, that is as follows:-

  1. Silent (1928 – 1945)
  2. Boomers (1946 – 1964)
  3. Gen X (1965 – 1980)
  4. Millennials (1981 – 1996)

So as per the above mentioned understandings there are various options kept wide open for the LibreOffice devs to work upon. The choices that they make will reflect in the upcoming future releases.

Just to note that the new feature is arriving in Jan 2017 with the release stated 5.3 which shall be stable in January of the next year(as mentioned during the time of writing the article). Now in case if you’re running a stable version or a version prior to 5.3 then you’re out of luck.But if you’re rocking a pre-release version you can try it out. How to enable the ‘LibreOffice Ribbon’? First, click through to enable the “notebook bar” feature under:

  • Tools = > Options = > LibreOffice General = > Advanced = > Experimental features

Once enabled head back to the main LibreOffice app. To enable (turn on) the Notebook bar click:

  • View = > Toolbar Layout = > Default/Single toolbar/Sidebar/Notebookbar

That’s it for now, hope to see all this feature rolled out soon next year !

 

Image courtesy :- OmgUbuntu.co.uk