How to Use Python NumPy Array – Linux Hint

Many libraries exist in Python to perform different types of tasks. NumPy is one of them. The full form of NumPy is Numerical Python, and it is mainly used for scientific computing. Multi-dimensional array objects can be defined by using this library that is called the Python NumPy array. Different types of functions exist in the NumPy library to create the array. NumPy array can be generated from the python list of numeric data, range of data, and random data. How NumPy array can be created and used to do different operations types have shown in this tutorial.

How to Use Python NumPy arange() Function – Linux Hint

Many functions exist in the Python NumPy library to perform different types of numerical and scientific operations. Creating different types of arrays for various purposes is one of the practical uses of the NumPy library. Python has a built-in function named arange() to create a list of sequential numbers. arange() is one of the array creation functions of the NumPy library to create an array of numeric ranges. The uses of the NumPy arange() function have explained in this tutorial.

How to Use Python NumPy reshape() Function – Linux Hint

NumPy library has many functions to work with the multi-dimensional array. reshape () function is one of them that is used to change the shape of any existing array without changing the data. The shape defines the total number of elements in each dimension. The array’s dimension can be added or removed, and the number of elements in each dimension can be modified by using the reshape() function. The one-dimensional array can be converted into a multi-dimensional array, but the multi-dimensional array can’t be converted into a one-dimensional array by this function. How to reshape() function works and its uses are explained in this tutorial.

How to Use Python NumPy zeros() and ones() Functions – Linux Hint

NumPy library is one of the useful libraries of python that can be used to create arrays. zeros() and ones() are the NumPy library functions to create two different arrays. zeros() function is used to create an array based on the particular shape and type. All array elements are initialized to 0, which is created by the zeros() function. ones() function works like the zeros() function. But the elements of the array created by the ones() function are initialized to 1. The uses of both functions have shown in this tutorial by using multiple examples.

How to convert Python NumPy array to python list – Linux Hint

Array object is used to store multiple values, and the list object is used in Python to do a similar task to an array object. NumPy array object is used to do different types of numerical operations in Python. The multi-dimensional array can be created by using this library. NumPy library has a built-in tolist() function to convert the NumPy array to the python list. This function does not take any argument and returns the python list. If the array is one-dimensional, then the function will return a simple python list. If the array is multi-dimensional, then the array will return the nested python list. If the array’s dimension is 0, then the function will return a python scalar variable instead of a list. How tolist() function can convert different types of NumPy array to python list is shown in this tutorial.

How to install NumPy python development environment on Ubuntu – Linux Hint

Python is a modern programming language now for supporting a large number of libraries. Various types of tasks can be done by using these libraries. NumPy is one of the useful libraries of Python to perform scientific operations. This library can be used to create a multi-dimensional array of objects. Different types of mathematical tasks can be done quickly using this library, such as sorting the array, reshaping array, statistical operation, arithmetical operations, etc. It works faster because it is developed by using the C programming language.

Python Unittest Tutorial

Unit testing is a testing method used in software engineering for individual units of any code. Users can put the individual tests to determine the status of the source and how much the code is suitable to be used. This way users can test the code quality.

Testing is done once the process of development is complete. Users can also begin testing when the test script is to be verified based on the criteria of the testing. Developers are expected to write the manual types of the source code. Generally, manually writing unit testing codes is a hectic task but in Python, it is done using an in-built function called unittest.

How to test PHP code using PHPUnit - Anto ./ Online

PHPUnit automatically executable tests that verify your application’s behavior. Thus – you can ensure that your changes don’t break existing functionality. This post will show you how to test your PHP code using PHPUnit.

Latency Numbers Every Team Should Know

We design systems around the size of delays that are expected. You may have seen the popular table “latency numbers every programmer should know” which lists some delays that are significant in technology systems we build.

Teams are systems too. Delays in operations that teams need to perform regularly are significant to their effectiveness. We should know what they are.

Ssh to a server on the other side of the world and you will feel frustration; delay in the feedback loop from keypress to that character displayed on the screen.

Here’s some important feedback loops for a team, with feasible delays. I’d consider these delays tolerable by a team doing their best work (in contexts I’ve worked in). Some teams can do better, lots do worse.

[...]

In recent times you may have experienced the challenge of having conversations over video links with significant delays. This is even harder when the delay is variable. It’s hard to avoid talking over each other.

Similarly, it’s pretty bad if we know it’s going to take all day to deploy a change to production. But it’s so worse if we think we can do it in 10 minutes, when it actually ends up taking all day. Flaky deployment checks, environment problems, change conflicts create unpredictable delays.

It’s hard to get anything done when we don’t know what to expect. Like trying to hold a video conversation with someone on a train that’s passing through the occasional tunnel.

How I programmed a virtual gift exchange

Every year, my wife's book club has a book exchange during the holidays. Due to the need to maintain physical distance in 2020, I created an online gift exchange for them to use during a book club videoconference. Apparently, the virtual book exchange worked out (at least, I received kind compliments from the book club members), so I decided to share this simple little hack.

Dirk Eddelbuettel: prrd 0.0.4: More tweaks

The key idea of prrd is simple, and described in some more detail on its webpage and its GitHub repo. Reverse dependency checks are an important part of package development that is easily done in a (serial) loop. But these checks are also generally embarassingly parallel as there is no or little interdependency between them (besides maybe shared build depedencies). See the (dated) screenshot (running six parallel workers, arranged in split byobu session).

This release brings several smaller tweaks and improvements to the summary report that had accumulated in my use since the last release last April. We also updated the CI runners as one does these days.

vrurg: A New Release Of Cro::RPC::JSON

I don’t usually announce regular releases of my modules. But not this time. I start this new year with the new v0.1 branch of Cro::RPC::JSON. Version 0.1.1 is currently available on CPAN (will likely be replaced with fez as soon as it is ready). The release is a result of so extensive changes in the module that I had to bump its :api version to 2.

gfldex: Anonymous slurpers

I have a script where I’m only interested in the last two lines of its output.

Eclipse OpenJ9 0.24 Released With A Ton Of Improvements - Phoronix

In addition to Oracle's GraalVM 21.0 being released this week, the Eclipse Foundation has released OpenJ9 v0.24 as the newest feature release for their high performance JVM.

The 10 most popular programming languages, according to Microsoft-owned GitHub [Ed: Why do some sites still reinforce the bogus idea that only projects that Microsoft controls using an oppressive and proprietary monopoly count or exist?]

Carlos Garnacho: Threaded input adventures

Mutter wasn’t always a self-contained compositor toolkit, in the past it used to rely on Clutter and Cogl libraries for all the benefits usually brought by toolkits: Being able to draw things on screen, and being able to receive input.

In the rise of Wayland, that reliance on an external toolkit drove many of the design decisions around input management, usually involving adding support in the toolkit, and the necessary hooks so Mutter could use or modify the behavior. It was unavoidable that both sides were involved.

Later on, Mutter merged its own copies of Clutter and Cogl, but the API barrier stayed essentially the same at first. Slowly over time, and still ongoing, we’ve been refactoring Mutter so all the code that talks to the underlying layers of your OS lives together in src/backends, taking this code away from Clutter and Cogl.

Partially-Formed @ Meeting C++ 2021 talk is now online

We will also show how developers that feel uneasy about the partially-formed state can avoid them at little to no cost, neither in code readability, nor performance, and use these examples to propose a new (or old) paradigm for API design: safe and unsafe functions (in the Sean Parent sense).

How to implement a DevOps toolchain

Organizations from all industries and of all sizes strive to deliver quality software solutions faster. This guarantees not only their survival but also success in the global marketplace. DevOps can help them chart an optimal course.

DevOps is a system where different processes are supported by tools that work in a connected chain to deliver projects on time and at a lower cost.

What is your favorite Linux scripting or programming language? | Enable Sysadmin

Of all the scripting and programming language options available to you on the Linux platform, which one is your favorite?

When costs are nonlinear, keep it small.

It shows Preventive Maintenance as a series of small costs. Minor repairs are a series of bigger costs, and major repairs are much bigger than that. Every maintenance delayed escalates into a minor repair and then a major repair — costs increase nonlinearly with time delay.

Old compilers and old bugs

The kernel project goes out of its way to facilitate building with older toolchains. Building a kernel on a new system can be enough of a challenge as it is; being forced to install a custom toolchain first would not improve the situation. So the kernel developers try to keep it possible to build the kernel with the toolchains shipped by most distributors. There are costs to this policy though, including an inability to use newer compiler features. But, as was seen in a recent episode, building with old compilers can subject developers to old compiler bugs too.

On January 5, Russell King reported on a problem he had been chasing for a long time. Some of his 64-bit Arm systems running 5.4 or later kernels would, on rare occasion, report a checksum failure on the ext4 root filesystem. It could take up to three months of uptime for the problem to manifest itself, making it, as King described it, "unrealistic to bisect". He had, however, found a way to more reliably reproduce the failure, making the task of finding out when the problem was introduced plausible, at least.

Starting with King's findings, a number of developers working in the Arm subsystem looked into the issue; their efforts seemed to point out this commit as the culprit. That change, applied in 2019, relaxed the memory barriers used around I/O accessors, optimizing accesses to I/O memory. Reverting this patch made the problem go away.

Callback Function in C++ – Linux Hint

A callback function is a function, which is an argument, not a parameter, in another function. The other function can be called the principal function. So two functions are involved: the principal function and the callback function itself. In the parameter list of the principal function, the declaration of the callback function without its definition is present, just as object declarations without assignment are present. The principal function is called with arguments (in main()). One of the arguments in the principal function call is the effective definition of the callback function. In C++, this argument is a reference to the definition of the callback function; it is not the actual definition. The callback function itself is actually called within the definition of the principal function.

The basic callback function in C++ does not guarantee asynchronous behavior in a program. Asynchronous behavior is the real benefit of the callback function scheme. In the asynchronous callback function scheme, the result of the principal function should be obtained for the program before the result of the callback function is obtained. It is possible to do this in C++; however, C++ has a library called future to guarantee the behavior of the asynchronous callback function scheme.

Regarding the closure of rt.cpan.

Let me preface this short post with this, I don't have the solution to this problem. Perhaps there is someone in the wider Perl space who is well placed to pick this up, but there seems to be little going on in terms of community engagement.

In the first week of 2021 I noticed a link to this sunset message for rt.cpan behind displayed on the rt.cpan homepage. Firstly I believe the notification on the page could be highlighted better, grey on grey, on a page with lots of grey isn't exactly eye catching.

At the time the linked article didn't contain much information, besides a date. It has since been updated with links to resources to migrate tickets elsewhere.

A reply to my post in the perlmonks news section was concerning to me, I shortly found the infrastructure working group post on topicbox (which I find no link to on any of the perl websites, or release documentation). This thread was concerning in so much as a single volunteer has decided to step back, which is of course fine, but it doesn't seem like the option of asking the wider community if anyone would be willing to step up and take it over has been explored. It doesn't even seem to be being openly discussed.

Perl weekly challenge 096 - Raku

GNU Linux Bash – script for troubleshoot long term test testing network internet connection connectivity

this script is intended for long term testing of reliability of network connection/connectivity