OpenLLM-France/wikimedia huggingface dataset:
# Linux Administration/Installation/Debian Packages

This lesson covers Debian package manager software.

## Objectives and Skills

Objectives and skills for the Debian packages portion of Linux+ certification include:
* Use Debian package management
** Install, upgrade and uninstall Debian binary packages
** Find packages containing specific files or libraries that may or may not be installed
** Obtain package information such as version, content, dependencies, package integrity and installation status (whether or not the package is installed)
** The following is a partial list of the used files, terms and utilities:
*** /etc/apt/sources.list
*** dpkg
*** dpkg-reconfigure
*** apt-get
*** apt-cache
*** aptitude

## Readings

* Wikipedia: deb (file format)
* Wikipedia: dpkg
* Wikipedia: APT (Debian)
* Wikipedia: aptitude (software)

## Activities

* Complete the tutorial IBM: Learn Linux, 101: Debian package management

## Lesson Summary

* Advanced Package Tool, or APT, is a free-software user interface that works with core libraries to handle the installation and removal of software on Debian, Ubuntu, and related Linux distributions.
* apt-get update is used to re-synchronize the package index files from their sources.
* apt-get upgrade is used to install the newest versions of all packages currently installed on the system from the sources enumerated in /etc/apt/sources.list.
* apt-get dist-upgrade Performs smart upgrade with dependency conflict resolution.
* apt-get install packagelist installs listed packages.
* apt-get remove packagelist removes listed packages.
* apt-cache searches and generates package metadata.
* apt-cache showpkg packagelist displays package information and reverse dependencies.
* dpkg -l lists all packages installed on a system.
* dpkg -L package lists the files installed by a given package.
* dpkg -S filename lists the package that installed a given file.
* sudo dpkg -i filename.deb installs a local .deb file.
* dpkg-deb packs, unpacks and provides information about Debian archives.
* dselect was the primary user interface for installing, removing and managing Debian packages. It is the traditional front-end to dpkg.
# Linux Administration/Installation/RPM and YUM Packages/Read RPM release notes

* 09/2019 RPM 4.15.0 Release notes: https://rpm.org/wiki/Releases/4.15.0.html
** Support building rpm without Berkeley DB: –disable-bdb
* RPM 4.14.2.1 Release notes, https://rpm.org/wiki/Releases/4.14.2.1
* RPM 4.14.2 Release notes, https://rpm.org/wiki/Releases/4.14.2
* RPM 4.14.1 Release notes
* RPM 4.14.0 Release notes
# Linux Administration/Devices and Filesystems/ZFS

ZFS is a combined file system and volume manager included in Solaris 10 update 2 (06/2006) and Ubuntu 16.04 LTS onwards. ZFS support advances features such as
* Data integrity
* Integrated volume management – zpool (pooled storage)
* Copy on Write (CoW)
* Compression
* Snapshots and clones
* Deduplication
* Solaris: Online shrink zpool remove in Solaris 11.4 released in August 2018
Commands: zfs, zpool, zdb

## Configuration files

* /etc/default/zfs

## Commands

* List your block/disk devices: lsblk or lsblk -f or fdisk -l
* Show pool status: zpool status
* List ZFS pools : zpool list
       zpool list -v
* zfs mount -a
* zfs umount
Create a new pool:
* Create a new pool: sudo zpool create DATA /dev/sdbbbbbbb11
* Create a new stripped pool: sudo zpool create MY-NEW-STRIPPED-POOL /dev/sdb /dev/sdc
* Create a new mirrored pool: sudo zpool create MY-NEW-MIRROR-POOL mirror /dev/sdb /dev/sdc
To Modify Disk identification to use disk/by-id:
* zpool export DATA
* zpool import -d /dev/disk/by-id DATA
* Verify: zdb -C

### Pools

* zpool destroy YOUR_POOL
* Show pool status: zpool status
* List ZFS pools : zpool list

### Filesystems

* Create a new filesystem: sudo zfs create DATA/datafs
* Destroy a zfs filesystem: sudo zfs destroy DATA/datafs_TO_DESTROY (Warning: no confirmation requested)
** sudo zfs destroy -r DATA/datafs_TO_DESTROY
* Set a quota to a filesystems: zfs set quota=50G pool/home/bob
* Check zfs service status: systemctl status "zfs*" "zpool*"
* Display configuration information: zdb -C

### List information

* Show pool status: zpool status
* List ZFS pools : zpool list
* List FS/Volumens/snapshots: zfs list
* zfs get all
       zfs get all | grep mountpoint

### Advanced

* zpool import

## Activities

* Read selecting dev names when creating a pool before you create your first ZFS pool: https://github.com/zfsonlinux/zfs/wiki/FAQ#selecting-dev-names-when-creating-a-pool and https://wiki.archlinux.org/index.php/Persistent_block_device_naming
* Read ArchLinux documentation about ZFS: https://wiki.archlinux.org/index.php/ZFS#Creating_a_storage_pool
* Follow Ubuntu Tutorial about Setup a ZFS storage pool: https://tutorials.ubuntu.com/tutorial/setup-zfs-storage-pool#0
* Create you first ZFS pool: zpool create
# Linux Administration/Installation/Boot Manager

This lesson covers boot management.

## Objectives and Skills

Objectives and skills for the boot manager portion of Linux+ certification include:
* Install a boot manager
** Providing alternative boot locations and backup boot options
** Install and configure a boot loader such as GRUB Legacy
** Perform basic configuration changes for GRUB 2
** Interact with the boot loader
** The following is a partial list of the used files, terms and utilities:
*** menu.lst, grub.cfg and grub.conf
*** grub-install
*** grub-mkconfig
*** MBR

## Readings

* Wikipedia: GNU GRUB
* Wikipedia: Master boot record
* Wikibooks: LPI Linux Certification/Install A Boot Manager
* Linux.com: How to Rescue a Non-booting GRUB 2 on Linux

## Multimedia

* YouTube: Working with GRUB Legacy

## Activities

* Complete the tutorial IBM: Learn Linux, 101: Install a boot manager
* Complete the tutorial OpenSource: An introduction to GRUB2 configuration for your Linux machine
* Review Linoxide: How to Set Linux Grub Password with Examples. Set a GRUB password on your test system.
* Review HowToGeek: How to Configure the GRUB2 Boot Loader’s Settings. Set GRUB to boot automatically after 10 seconds.

## Lesson Summary

* The command grub-mkpasswd-pbkdf2 generates an encrypted password for GRUB.
# Linux Administration/Devices and Filesystems/Partitions

This lesson covers partitions.

## Objectives and Skills

Objectives and skills for the partitions portion of Linux+ certification include:
* Create partitions and file systems
** Manage MBR partition tables
** Use various mkfs commands to create various file systems such as:
*** ext4 or deprecated ext2/ext3
*** XFS
*** VFAT
** Awareness of ReiserFS and Btrfs
** Basic knowledge of gdisk and parted with GPT
** The following is a partial list of the used files, terms and utilities:
*** fdisk
*** gdisk
*** parted
*** mkfs (mkfs.btrfs mkfs mkfs.bfs mkfs.cramfs mkfs.ext2 mkfs.ext3 mkfs.ext4 mkfs.fat mkfs.minix mkfs.msdos mkfs.ntfs mkfs.vfat mkfs.xfs)
*** mkswap
*** lsblk, included in Util-linux package, to identify and list your block devices such as Hard Disks (HDD)

## Readings

* Wikipedia: Disk partitioning

## Activities

* Complete the tutorial IBM: Learn Linux, 101: Create partitions and filesystems
* Review RedHat 7 Documentation about Creating an ext4 filesystem
# Linux Administration/Devices and Filesystems/Permissions

This lesson covers permissions.

## Objectives and Skills

Objectives and skills for the permissions portion of Linux+ certification include:
* Manage file permissions and ownership
** Manage access permissions on regular and special files as well as directories
** Use access modes such as suid, sgid and the sticky bit to maintain security
** Know how to change the file creation mask
** Use the group field to grant file access to group members
** The following is a partial list of the used files, terms and utilities:
*** chmod
*** umask
*** chown
*** chgrp

## Readings

* Wikipedia: File system permissions

## Activities

* Complete the tutorial IBM: Learn Linux, 101: Manage file permissions and ownership
# Linux Administration/Installation/RPM and YUM Packages

This lesson covers RPM and YUM package managers.

## Objectives and Skills

Objectives and skills for the RPM and YUM packages portion of Linux+ certification include:
* Use RPM and YUM package management
** Install, re-install, upgrade and remove packages using RPM and YUM
** Obtain information on RPM packages such as version, status, dependencies, integrity and signatures
** Determine what files a package provides, as well as find which package a specific file comes from
** The following is a partial list of the used files, terms and utilities:
*** rpm
*** rpm2cpio
*** /etc/yum.conf
*** /etc/yum.repos.d/
*** yum
*** yumdownloader

## Readings

* Wikipedia: RPM Package Manager
* Wikipedia: yum (software)

## Activities

* Complete the tutorial IBM: Learn Linux, 101: RPM and YUM package management
* Read RPM release notes

## Lesson Summary

* RPM Package Manager (RPM) (originally Red Hat Package Manager) is a free and open-source package management system using the .rpm file format.
* rpm -i package installs the given package.
* rpm -U package upgrades the given package.
* rpm -F package freshens (reinstalls) the given package.
* rpm -e package erases (removes) the given package.
* rpm2cpio extracts RPM payload files without having to install the package.
* The Yellowdog Updater, Modified (YUM) is a free and open-source command-line package-management utility for computers running the Linux operating system using the RPM Package Manager.
* yum install packagelist installs the given packages.
* yum update packagelist updates the given packages.
* yum remove packagelist removes the given packages.
* yumdownloader is a program for downloading RPMs from Yum repositories.
* /etc/yum.conf is the configuration file used by yum.
* /etc/yum.repos.d/ is the yum repository directory.
# Linux Administration/Installation

This section of the Linux Administration course covers installation. Lessons include Disk Layout, Boot Manager, Shared Libraries, Debian Packages, and RPM and YUM Packages.

## Preparation

Learners should already be familiar with introductory computer concepts, computer support concepts, and computer networking concepts.

## Lessons

* Disk Layout
* Boot Manager
* Shared Libraries
* Package managers
** Debian Packages
** RPM and YUM Packages

## See Also

* Linux
# Linux Administration/Installation/Disk Layout

This lesson covers disk layout.

## Objectives and Skills

Objectives and skills for the disk layout portion of Linux+ certification include:
* Design hard disk layout
** Allocate file systems and swap space to separate partitions or disks
** Tailor the design to the intended use of the system
** Ensure the /boot partition conforms to the hardware architecture requirements for booting
** Knowledge of basic features of Logical Volume Manager (LVM)
** The following is a partial list of the used files, terms and utilities:
*** /(root) filesystem
*** /var filesystem
*** /home filesystem
*** /boot filesystem
*** swap space
*** mount points
*** partitions

## Readings

* Wikipedia: Disk partitioning
* Wikipedia: System partition and boot partition
* Wikipedia: Paging
* Wikipedia: Logical Volume Manager (Linux)
* Wikipedia: Mount (computing)
* Wikipedia: ZFS (Combined filesystems and Logical Volume Manager)

## Multimedia

* YouTube: Linux Partitions and File System Layouts

## Activities

* Complete the tutorial IBM: Learn Linux, 101: Hard disk layout

## Key Terms
### inode (index node)

    A data structure in a Unix-style file system that describes a file-system object such as a file or a directory.
# Other Free Learning Resources

This project (formerly the "Hunter-gatherers project") aims to find, list, and evaluate Internet learning resources that anyone can freely access and use. We encourage you to discuss and explore ways to integrate these resources with Wikiversity courses. These are important tasks and essential aspects of Wikiversity's purpose.
# Other Free Learning Resources/Mathematics

The Wikiversity Hunter-gatherers project is devoted to finding learning resources on the internet. An important function of Wikiversity is to provide critical evaluations of learning materials and online learning resources. Hunter-gatherers should participate in the critical evaluation of learning resources by editing the Wikiversity pages that are devoted to evaluating learning materials and describing how to integrate them into courses of study.

## Online resources for mathematics

List good online mathematics learning resources below. Be sure to link to these resources from the appropriate Wikiversity pages.
* Khan Academy
* ThatQuiz - Math test activities for students and teachers of all grade levels
* The Statistics Homepage (Statsoft)
* hotmath
* webmath
* Math is Fun
* Biographies of Mathematicians
* Math tests bank of math tests online
* "A Compilation of Useful, Free, Online Math Resources"
* "List of Interactive Math Websites"
* Cut-The-Knot
* The Mathematical Genius in You: a peer-support math group
* Euclidea: geometric proofs
* Math Planet math exercises and lessons
* Symbolab Math problem solver
* Wolframalfa Man exercises
# Outcome mapping/Activities

Outcome mapping Nav

## Background Reading

Start by exploring the Resources, surf the web, ... and then add some activities here for fellow learners to follow in your footsteps, or to explore alternative pathways ...

## Learn by Doing

Apply Outcome Mapping in you project, share your thoughts and outputs during the process, write up the results and share your case study on the Case Studies page.
# Outcome mapping/Community

Outcome mapping Nav
Feel free to take this over with a few friends and grow a WikiEducator community around outcome mapping.
# Outcome mapping

Outcome mapping Nav
* Type classification: this resource is a course.
* Completion status: this resource is a stub, so not much has been done yet.
* Educational level: this is a non-formal education resource.
* Educational level: this is a tertiary (university) resource.
* Orientation
* Where are we going with this?
* This course started as a module of the SSE curriculum under Valuation. Feel free to expand it to become a comprehensive module on Outcome Mapping for more general purposes.
* more
* Preparation
* Recommended preparation
* Take a look at the Resources pages and find introductory readings.
* more
* Tips
* Reminders
* Navigation
* Educators
* Learners
* more
* Growth Opportunity
* Include ...
* Get up to speed with current thinking on programme development methodology
* Learn about one the most effective approaches available, and
* acquire the facilitation and other skills to participate meaningfully in development programmes which use the approach.
* more
* Guidance
* Getting there
* Read about Outcome Mapping
* Discuss it with peers and experts
* Participate in workshops
* Co-facilitate
* Record your learning.
* more
* Next
* Next step
* Start with the learning Activities ...
* more
# Outcome mapping/Go

Start with the learning Activities ...
# Outcome mapping/Go/more

Additional/alternative first steps and alternative learning pathways ...
# PlanetPhysics/Derivation of Wave Equation

Let a string of homogeneous matter be tightened between the points \,$x=0$\, and\, $x=p$\, of the $x$-axis and let the string be made vibrate in the $xy$-plane.\, Let the line density of mass of the string be the constant $\sigma$.\, We suppose that the amplitude of the vibration is so small that the tension ${\vec {T}}$ of the string can be regarded to be constant.
The position of the string may be represented as a function $y\;=\;y(x,\,t)$ where $t$ is the time.\, We consider an element $dm$ of the string situated on a tiny interval \, $[x,\,x\!+\!dx]$;\, thus its mass is $\sigma \,dx$.\, If the angles the vector ${\vec {T}}$ at the ends $x$ and $x\!+\!dx$ of the element forms with the direction of the $x$-axis are $\alpha$ and $\beta$, then the scalar components of the resultant force ${\vec {F}}$ of all forces on $dm$ (the gravitation omitted) are $F_{x}\;=\;-T\cos \alpha +T\cos \beta ,\quad F_{y}\;=\;-T\sin \alpha +T\sin \beta .$ Since the angles $\alpha$ and $\beta$ are very small, the ratio ${\frac {F_{x}}{F_{y}}}\;=\;{\frac {\cos \beta -\cos \alpha }{\sin \beta -\sin \alpha }}\;=\;{\frac {-2\sin {\frac {\beta -\alpha }{2}}\sin {\frac {\beta +\alpha }{2}}}{2\sin {\frac {\beta -\alpha }{2}}\cos {\frac {\beta +\alpha }{2}}}},$ having the expression \,$-\tan {\frac {\beta +\alpha }{2}}$, also is very small.\, Therefore we can omit the horizontal component $F_{x}$ and think that the vibration of all elements is strictly vertical.\, Because of the smallness of the angles $\alpha$ and $\beta$, their sines in the expression of $F_{y}$ may be replaced with their tangents, and accordingly $F_{y}\;=\;T\cdot (\tan \beta -\tan \alpha )\;=\;T\,[y'_{x}(x\!+\!dx,\,t)-y'_{x}(x,\,t)]\;=\;T\,y''_{xx}(x,\,t)\,dx,$ the last form due to the mean-value theorem.
On the other hand, by Newton the force equals the mass times the acceleration: $F_{y}\;=\;\sigma \,dx\,y''_{tt}(x,\,t)$
Equating both expressions, dividing by $T\,dx$ and denoting\, ${\sqrt {\frac {T}{\sigma }}}=c$,\, we obtain the partial differential equation
   ${\begin{matrix}y''_{xx}\;=\;{\frac {1}{c^{2}}}y''_{tt}\end{matrix}}$
for the equation of the transversely vibrating string.\\
But the equation (1) don't suffice to entirely determine the vibration.\, Since the end of the string are immovable,the function\, $y(x,\,t)$\, has in addition to satisfy the boundary conditions
   ${\begin{matrix}y(0,\,t)\;=\;y(p,\,t)\;=\;0\end{matrix}}$
The vibration becomes completely determined when we know still e.g. at the beginning\, $t=0$\, the position $f(x)$ of the string and the initial velocity $g(x)$ of the points of the string; so there should be the initial conditions
   ${\begin{matrix}y(x,\,0)\;=\;f(x),\quad y'_{t}(x,\,0)\;=\;g(x).\end{matrix}}$
The equation (1) is a special case of the general wave equation
   ${\begin{matrix}\nabla ^{2}u\;=\;{\frac {1}{c^{2}}}u''_{tt}\end{matrix}}$
where\, $u=u(x,\,y,\,z,\,t)$.\, The equation (4) rules the spatial waves in $\mathbb {R}$.\, The number $c$ can be shown to be the velocity of propagation of the wave motion.
# PlanetPhysics/Derivation of Cohomology Group Theorem
### Introduction

Let $X_{g}$ be a general CW-complex and consider the set $\left\langle {X_{g},K(G,n)}\right\rangle$ of basepoint preserving homotopy classes of maps from $X_{g}$ to Eilenberg-MacLane spaces $K(G,n)$ for $n\geq 0$, with $G$ being an Abelian group.
\begin{theorem}(Fundamental, [or reduced] cohomology \htmladdnormallink{theorem {http://planetphysics.us/encyclopedia/Formula.html},}).
There exists a natural group isomorphism:
   $\iota :\left\langle (X_{g},K(G,n))\right\rangle \cong {\overline {H}}^{n}(X_{g};G)$
for all CW-complexes $X_{g}$ , with $G$ any Abelian group and all $n\geq 0$. Such a group isomorphism has the form $\iota ([f])=f^{*}(\Phi )$ for a certain distinguished class in the cohomology group $\Phi \in {\overline {H}}^{n}(X_{g};G)$, (called a ""fundamental class ).
\end{theorem}

### Derivation of the cohomology group theorem for connected CW-complexes.

For connected CW-complexes, $X$, the set $\left\langle X_{g},K(G,n))\right\rangle$ of basepoint preserving homotopy classes maps from $X_{g}$ to Eilenberg-MacLane spaces $K(G,n)$ is replaced by the set of non-basepointed homotopy classes $[X,K(\pi ,n)]$, for an Abelian group $G=\pi$ and all $n\geq 1$, because every map $X\to K(\pi ,n)$ can be homotoped to take basepoint to basepoint, and also every homotopy between basepoint -preserving maps can be homotoped to be basepoint-preserving when the image space $K(\pi ,n)$ is simply-connected.
Therefore, the natural group isomorphism in {\mathbf Eq. (0.1)} becomes:
   $\iota :[X,K(\pi ,n)]\cong {\overline {H}}^{n}(X;\pi )$
When $n=1$ the above group isomorphism results immediately from the condition that $\pi =G$ is an Abelian group. QED {\mathbf Remarks.}
* A direct but very tedious proof of the (reduced) cohomology theorem can be obtained by constructing maps and homotopies cell-by-cell.
* An alternative, categorical derivation via duality and generalization of the proof of the cohomology group theorem is possible by employing the categorical definitions of a limit, colimit/cocone, the definition of Eilenberg-MacLane spaces (as specified under related), and by verification of the axioms for reduced cohomology groups (pp. 142-143 in Ch.19 and p. 172 of ref.).
This also raises the interesting question of the propositions that hold for non-Abelian groups G, and generalized cohomology theories.
\begin{thebibliography} {9}
</ref></references>
* 1 2 Hatcher, A. 2001. Algebraic Topology., Cambridge University Press; Cambridge, UK., (Theorem 4.57, pp.393-405).
* 1 2 3 May, J.P. 1999, A Concise Course in Algebraic Topology. , The University of Chicago Press: Chicago
# PlanetPhysics/Dalton's Law

The gases are mixable with each other in all proportions.\, Since the ideal gas law
   ${\begin{matrix}pV=nRT\end{matrix}}$
is valid for any ideal gas, one may think that it's insignificant whether the mole number $n$ concerns one single gas or several gases.\, It is true, which can be shown experimentally.
Let's think that we mix the volumes $V_{1}$, $V_{2}$, ..., $V_{k}$ of different gases having an equal pressure $p$ and an equal temperature $T$.\, If one measures the volume $V$ of the mixture in the same pressure and temperature, one notices that $V=V_{1}\!+\!V_{2}\!+\!...\!+\!V_{k}.$ Each of the gases satisfies an equation\, $pV_{i}=n_{i}RT$,\, and thus
   ${\begin{matrix}pV=pV_{1}\!+\!pV_{2}\!+\!...\!+\!pV_{k}=(n_{1}\!+\!n_{2}\!+\!...\!+\!n_{k})RT.\end{matrix}}$
This is similar as the general equation (1).\, If we think that the same volume $V$ would be filled by any of the gases alone, we had an equation $p_{i}V=n_{i}RT$ for each gas; here the pressure $p_{i}$, i.e. $n_{i}{\frac {RT}{V}}$, is called the partial pressure of the gas $i$.\, By (2), we have $p=(n_{1}\!+\!n_{2}\!+\!...\!+\!n_{k}){\frac {RT}{V}}=n_{1}{\frac {RT}{V}}\!+\!n_{2}{\frac {RT}{V}}\!+\!...\!+\!n_{k}{\frac {RT}{V}}=p_{1}\!+\!p_{2}\!+\!...\!+\!p_{k}.$ Accordingly we have obtained the
Dalton's law. \, The pressure of a gas mixture is equal to the sum of the partial pressures of the component gases.
This law was invented by J. Dalton in 1801.
# PlanetPhysics/Density Matrix

\setcounter{section}{1}
A density matrix $\rho$ is a matrix representing the density operator with the conditions:
* The trace of $\rho$ is $1$.
* $\rho$ is a positive-semidefinite matrix
References
[1] MIT OpenCourseWare, 8.371J Quantum Information Science, Spring 2006.
[2]Blum, Karl, Density Matrix Theory and Applications . 2nd edition Springer, 1996.
# PlanetPhysics/Derivation of Coulomb's Law From Gauss Law

As an example of the statement that Maxwell's equations completely define electromagnetic phenomena, it will be shown that Coulomb's law may be derived from Gauss' Law for electrostatics. Consider a point charge of charge $q$; we can obtain an expression for the Electric Field at a point in space due to this charge by surrounding it with a "virtual" sphere of radius $R$, and then using the Gauss' law in integral form:
   $\oint _{S}\mathbf {E} \cdot \mathrm {d} \mathbf {A} ={\frac {q}{\epsilon _{0}}}{\mbox{ .}}$
The surface integral on the the right-hand-size of the equation can be written in spherical polar coordinates over the "virtual" sphere, considering the point charge at its centre. Under the assumption that the electric field is spherically symmetric, its value over the sphere surface is constant. Then, we can write
   $\oint _{S}\mathbf {E} \cdot \mathrm {d} \mathbf {A} =\int _{0}^{2\pi }\int _{0}^{\pi }R^{2}E\sin \theta \,d\theta \,d\phi ;$
hence,
   $4\pi R^{2}E={\frac {q}{\epsilon _{0}}},$
or
   $E={\frac {q}{4\pi \epsilon _{0}R^{2}}}.$
The usual form can then be recovered from the Lorentz force law $\mathbf {F} =\mathbf {E} q+\mathbf {v} \times \mathbf {B}$, noting the absence of magnetic field.