OpenLLM-France/wikimedia huggingface dataset:
# Linear Algebra/Cofactors and Minors
## Cofactors

Consider any column, the kth one. Consider all terms that contain the element a$_{ik}$, and factor out a$_{ik}$. The sum of all such terms is called the cofactor of a$_{ik}$, do be denoted Co(a$_{ik}$).
Every term contains exactly one element from the kth column. A determinant D can thus be written as a$_{1k}$Co(a$_{1k}$)+a$_{2k}$Co(a$_{2k}$)+a$_{3k}$Co(a$_{3k}$)+...a$_{nk}$Co(a$_{nk}$).
If, in fact the cofactors of a column or row were to be multiplied by some different column and row, its sum would be zero because it would be the same as a determinant with repeat columns and rows.
# Learn Baybayin/Reading and Writing

Kindly refer to the introduction for the full character chart.
Each letter has a vowel sound. By default, Baybayin letters are consonants with an inherent vowel "a". To produce another vowel sound, a special mark (known as a kudlít) is placed either on the top of the character (for "E" and "I" sounds) or at the bottom (for "O" and "U" sounds). The kudlít does not apply to stand-alone vowels, as they have their own characters.
In the original form, stand-alone consonants (consonants without the vowel sound) could not be formed. This was particularly hard for Spanish friars, who were working on translating books into Tagalog. In 1620, Father Francisco Lopez rectified the problem by inventing his own kudlít in the form of a cross sign ("+") that removed the vowel sound. The kudlít functions exactly the same way the virama functions in the Devanagari script used to write Hindi. This is called TAGALOG SIGN VIRAMA by Unicode.

## Exercise

After learning how to read and write the Baybayin script, you can now practice reading and writing Baybayin.
# Learn Baybayin
## Introduction

Baybayin (ᜊᜌ᜔ᜊᜌᜒᜈ᜔), was the pre-colonial Tagalog writing system that is a direct descendant of Kavi, the script used to write Old Javanese. It has seventeen characters where three of them are vowels (a, e/i, o/u).
Note: Baybayin script is an 'Abugida', not an 'Alphabet'. An abugida differs from an alphabet by the fact that in an abugida, any diacritics written above or below a character changes its readings.
Baybayin then and now Baybayin eventually died out as the Latin alphabet introduced by the Spaniards continued to be imposed in the colonial era. Nowadays, that script is used mainly for aesthetic purposes; on the Philippine banknotes, Philippine passport and sometimes in the logos of some Philippine agencies. Many Filipino politicians wanted to make it the national writing system of the Philippines. Many Filipinos are now learning it as a hobby.

## Exercise

Learn how to read and write Baybayin script, so you can practice reading and writing Baybayin.
# Learn Electronics
## Foreword

(Note book is under construction)
* Aim of book
* Prerequisites
* Materials

## Basics

* Basic Theory
* Open/Closed/Short Circuit
* Circuit Diagrams

## Resistors

* Materials - as Chapter 1, but add the multimeter (describe how to measure battery voltage) and high wattage resistors (or use some nichrome wire?; show circuit symbol).
* Voltage drop - connect in series with light bulb and observe drop in brightness, measure with multimeter.
* Ohms law - describe how to measure resistance, then calculate current from voltage drop, do an experiment to check.
* A couple more experiments here...

## Capacitors

* Materials
* Charging and Discharging
* more...

## Alternating Current

The previous chapters dealt with DC. This chapter gives a brief introduction to AC or Alternating Current. Although most people associate AC with the 120V or 230V outlets, it also involves any other electric signal which change polarity periodically e.g. audio signals. This chapter will address a small subset of AC signals: single phase AC as it's produced by the electricity company and delivered through the outlets in your home.
A note on safety: This chapter doesn't contain experiments. There are 2 reasons for this. First, any interesting experiments would require the use of an oscilloscope. Secondly, experimenting with electricity from an outlet is dangerous in so many ways: Death through electrocution, 3rd degree burns from electricity, house fire after a short circuit,... Schools have special infrastructure to be able to do such experiments in relative safety. Most of them would use a variable AC power supply rather than AC outlets anyway.

### What is AC?

This image shows a typical AC signal. How this signal changes over time is shown. If you've had trigonometry you'll notice the typical shape of the sinus function.
This image shows the amplitude of the AC signal, denoted as Um. This is the highest value the signal reaches.
If you look at the 2 lines marked with the T, you'll see they connect 2 identical points on the sine curve. The time it takes to get from the first to the second point is called the period and is indicated with the symbol T. This is a time and therefore expressed in seconds (or more likely milliseconds ms).
Frequency is the inverse of the period: f = 1 / T and is expressed in Hertz (Hz). It's defined as the number of periods per second.

## See also

* More about specific components
* Circuit Idea reveals the basic ideas behind circuits
* Circuit Theory
* Digital Circuits
* Semiconductors
# Learn Electronics/Alternating Current
## A (coil of) wire and a magnet, generating AC

Magnets attract iron and a few other metals, but here we are concerned with generating electricity. A simple experiment with iron filings and a magnet shows that there is such a thing as a magnetic field; that field is strongest (the force of attraction is highest) close to the poles of the magnet, and gets weaker further away from the poles.
A wire is usually made of copper, and copper is neither attracted nor repelled by a magnet, however if a wire, usually of copper, is inside a CHANGING magnetic field, or if the wire itself is moved to a place where the magnetic field is of DIFFERENT strength, then a voltage is generated between the two ends of that wire. If there are two wires that are connected in series, then that voltage will be twice as much, and if it is a coil, in that CHANGING magnetic field, with n number of turns, then the voltage will be n times as large. If a voltmeter is connected to the terminals of that coil, and the coil is moved, or the magnet is moved, then the voltage will be shown on the voltmeter. That voltage's direction will keep changing, it will ALTERNATE, as the changes are made, therefore that voltage is an Alternating Voltage, and if there is a circuit completed between the two terminals of the coil, then an Alternating Current (AC) will flow in that circuit.
* Usually one or more coils of wire are fixed on the outside of a circle, and an electromagnet is rotated inside, causing an alternating voltage and/or alternating current (AC) to be generated.
1 Think of a simple magnet that rotates; what happens? Starting with the magnet in a position so that the coil is half-way between the poles of the magnet, the magnetic field strength is zero at the coil, and therefore the voltage across the terminals of the coil is zero.
2. As the magnet rotates a little bit further, one of the poles gets closer to the coil, the fieldstrength changes, and therefore a voltage appears across the coil's terminals; the polarity of that voltage depends on how the voltmeter is connected; reversing the leads will reverse the indicated polarity of the voltage. Also the polarity depends on whether the North-pole or the South-pole is closest to the coil. Because the magnet rotates, its poles ALTERNATE getting closer to the coil, and therefore the indicated voltage ALTERNATES as well.
* Normally the resulting AC voltage is connected to a transformer in order to increase the voltage to a suitable level for transmission over great distances, but in addition there are sensors and switches designed to switch off if the current is too high, and also to ensure the rotation of the magnet or equivalent is then stopped - or else the speed of rotation would increase, causing considerable destruction, even, maybe, loss of life.
# Digital Circuits

Digital electronics handles digital signals. Digital signals are discrete signals. They have constant amplitude for a specific time period. Digital Circuits are a very important part of Electronics, and learning at least their basic concepts is highly recommended.

# See also

* Digital Circuits
* Elements of Digital Circuits
* TTL NOT and AND gates, just simple examples of the very many digital circuits.
* Analog circuits for comparison with digital circuits and digital Integrated Circuits (ICs).
* Digital to Analog & Analog to Digital Converters
* Communication systems Pros and Cons of Digital versus Analog.
* Digital Television and Mass Media
* Digital photography
* Electronics/Expanded Edition
* Signals and Systems/Time Domain Analysis/Sampling Theorem
From Wikipedia:
* Category (digital)
* Digital (the concept)
* Digital circuits
* Digital control
* Analog-to-digital converter
* Digital-to-analog converter
* Digitizing requires circuits to turn an analog signal into a digital representation of that signal.
* Digitizer converts an analog signal into a digital representation of the analog signal by sampling the analog signal.
* Electronics topics
From the Web:
* http://www.dspguide.com/filters.htm for "Introduction to Digital Filters". An example of what digital circuits are needed for.
Previous chapter Analogue and Digital | Next chapter: Microprocessors | Go back to Index
# Learn Baybayin/Practice

Try to transliterate these Tagalog words from Baybayin scripts into Latin alphabet.
* ᜊᜑᜄ᜔ᜑᜇᜒ
* ᜀᜐᜓ
* ᜑᜅᜒᜈ᜔
* ᜋᜓᜃ᜔ᜑ
* ᜉᜎᜌᜏ᜔
* ᜊᜓᜏᜈ᜔
* ᜉᜎᜌᜈ᜔
* ᜆᜄᜎᜓᜄ᜔
* ᜋᜄᜈ᜔ᜇ
* ᜐᜈ᜔ᜎᜒᜊᜓ
Try to transliterate these Tagalog words from Latin alphabet into Baybayin script.
* bihag
* dalampasigan
* ulam
* labanos
* sasakyan
* paaralan
* upuan
* gatas
* manok
* duyan

## Authors and Contributors

* Karl Basallote — started this book.
# Learn Electronics/Analogue and Digital

Analogue electronics handles analogue signals. Analogue signals are signals having continuously varying amplitudes with respect to the time. For example the loudspeaker of a TV set or of a radio receives a voltage that usually is continually changing, which in turn causes a current to flow that changes in the same way and that activates the speaker cone to move, causing sound. This is an analogue device.
Digital electronics handles digital signals. Digital signals are discrete signals. They have constant amplitude for a specific time period. Walking could be regarded as similar to a digital device. The number of steps per minute can vary, but each step is usually nearly the same. A digital signal can be regarded as a number "packages" that are almost the same, but the number of these packages that are delivered per minute varies.
In another context, there are analogue watches and digital watches. The analogue watches have a minute hand and an hour hand, they keep moving all the time, while a digital watch has numbers showing, they change only once in a while.

#### See also, from Wikipedia

* Analog signals
* Digital signals
Previous chapter Integrated Circuits | Next chapter: Digital Circuits | Go back to Index
# Lineage 2/The Player Character (PC) Classes & Character Guides/Rogue

Rogue is the thievery base class of the humans. They wear light armor and wield daggers or bows.

## Key Skills

Format: Name (Max. Level) - Description (Level[+Updates]/Next Level ...)

### Active

* Accuracy (1) - Increases Accurancy, costs MP. (24)
* Bleed (2) - Bleed Attack. Dagger Only. (24/32)
* Dash (1) - Temporarily increases atk speed. (20)
* Moral Blow (24) - Damage attack. Dagger only. (5+3/10+3/15+3/20+3/24+3/28+3/32+3/36+3)
* Power Shot (24) - Damage attack. Over-hit available. Bow only. (5+3/10+3/15+3/20+3/24+3/28+3/32+3/36+3)
* Relax (1) - Doubles HP regenertion while sitting, costs MP. (5)
* Stun Shot (3) - Stun and damage attack. Bow only. (36+3)
* Ultimate Evasion (1) - Increases Evasion while making movement impossible. (28)
* Unlock (5) - Opens doors and chests with increasing chances. (20/24/28/32/36)
* Vicious Stance (5) - Increases damage of critical attacks, costs MP. (20/24/28/32/36)

### Passive

* Acrobat (1) - Reduces damage from falling. (20)
* Acrobatic Move (1) - Increases Evasion while running. (28)
* Boost Attack Speed (1) - Increases Atk.Speed. (36)
* Boost Breath (1) - Increases lung capacity. (20)
* Boost Evasion (1) - Increases Evasion. (24)
* Bow Mastery (15) - Increases P.Atk. Bow only. (20+3/24+3/28+3/32+3/36+3)
* Critical Chance (1) - Increases chance of critical attacks. (28)
* Critical Power (2) - Increases damage of critical attacks. (24/32)
* Dagger Mastery (8) - Increases P.Atk. Dagger only. (20/24/28+2/32+2/36+2)
* Esprit (1) - Increased recovery while running. (36)
* Light Armor Mastery (10) - Increases P.Def. Light Armor only. (20+2/24+2/28+2/32+2/36+2)
* Long Shot (1) - Increases attack range. Bow only. (20)
* Quick Step (1) - Increases running speed. (28)
* Rapid Shot (1) - Increases attack speed. Bow only. (32)
* Vital Force (2) - Increases HP regeneration while sitting. (24/32)

### Outdated

* Armor Mastery (5) - Increase P.Def. (5/10+2/15+2)
* Weapon Mastery (3) - Increases P.Atk. (5/10/15)

## Development

As usual, focus on one of the two weapons if you dont have enough skillpoints for both. Still future THs should get the bow skills too, as those, unlike daggers, have an overhit-available skill, and its always nice to first use a bow on the enemy anyway.

## Equipment

Ideal would be of course the top d-grade light armor, Salamander skin, or the top d-grade set, Manticore skin, the later gives some additional mana, not an important bonus but better than nothing. The top d-grade dagger is the Mithril Dagger.

## Adventuring

An important feature of the human rogue classes is that they get the Vital Force skill, additional to Relax. This means that human rogues heal even faster while sitting than dwarves.
Dagger users simply do melee, while archers adventure like nukers - hit the mob, run away, hit the mob.
# Lineage 2/The Player Character (PC) Classes & Character Guides/Phantom Ranger

Phantom Rangers are the ranged fighters of the dark elves. They wear light armor and wield bows.

## Skills

- TODO -

## Development

- TODO -

## Equipment

The best weapon on c-grade is the Eminence Bow, best SA probably Cheap Shot. The best weapon on b-grade is the Bow of Peril, best SA probably Quick Recovery. The best weapon on a-grade is the Soul Bow, best SA probably Quick Recovery.
On c-grade the Plated Leather Set would be a great tool, as this one gives more damage and, being a ranged class, the PR has less requirement for maximum P.Def than others. Otherwise the Drake Leather Set would give a nice bonus on M.Def. On b-grade the Doom Light Set with its Dex bonus is probably best. On a-grade the Majestic Light Set has been made specifically for archers; stay away from Nightmare as its main Bonus, a small Vampiric Rage, doesnt work on bows.

## Adventuring

Archers are loners just like wizards. Combining them with their own class or with nukers works however well. Adding one of the elders for buffs, additional mana and a lot of healing power in emergency situations will improve such combos even more; with nukers the Shillien Elder with Empower is better, for archers alone the Elven Elder with Party Return, Agility and Resist Shock is to be prefered.
In normal parties archers can be integrated much like nukers. They have to be protected from being attacked by a tank using hate aura and aggression, and they should delay their attacks a bit from the rest of the group so the mob really has time to trigger on the tank.
# Lineage 2/The Player Character (PC) Classes & Character Guides/Phantom Summoner

Phantom Summoners are the 2nd class transfer for a dark elf wizard at lvl 40. they summon servitors, which can be thought of as fighting pets of sorts. the servitors require crystals and take a portion of the xp received, sometimes 30% sometimes even 90 %. the servitors or summons can allow the summoner to fight higher lvl mobs alone, allowing them to lvl up pretty fast.one person was a lvl 25 dark wizard with a basic servitor and his summon could fight portas and snipe cohorts in cruma tower.
# Lineage 2/The Player Character (PC) Classes & Character Guides/Prophet

Prophet are the specialized buffers in the game. They can use all weapons and all armor (even heavy).

## Key Skills

* Berserker Spirit – Increases casting speed, attacking speed, P.atk and M.atk while lowering P.def
* Bless Shield – Increases defense rate with shield
* Bless the Body – Increases max hp
* Bless the Soul - Increases max mp
* Death Whisper – Increases critical damage
* Focus – Increases critical rates
* Greater Acumen - Increases casting speed
* Greater Concentration – Decreases chance that the magic will be canceled due to damage
* Guidance - Increases Accuracy
* Haste - Increases Atk.Speed
* Invigor - Protects against Bleed
* Kiss of Eva - Increases Breath Gauge
* Magic Barrier – Increases M.def
* Mental Aegis - Protects against various attacks (Dryad Root etc)
* Might – Increases P.atk.
* Regeneration – Increases hp generation
* Resist Aqua - Resistance to water attacks
* Resist Fire - Resistance to fire attacks
* Resist Poison - Resistance against poison
* Resist Wind - Resistance against wind attacks
* Return - Teleport to nearest town
* Shield – Increases P. def
* Wind Walk - Increases moving speed

## Equipment

As they need so much Mana for buffing larger parties, and benefit so much from casting time speedups when doing the buffing, robes are actually very popular for Prophets.
Most prophets seem to prefer dual swords to deal a little damage while not buffing.

## Playstyle

As the prophet can buff so well plus can wear heavy armor, he is also the cleric who is best prepared to be played solo. At the same time, probably no other class gets a party as easily.

## Class Comparison

As of Chronicle 3 the only buffs really unique to prophets are Resist Fire, Resist Aqua, Berserk, Regeneration, Bless the Body, and Bless the soul. Warcryers have the group buffs for Shield, Might, Guidance, Focus, Death Whisper, Acumen, Haste, Windwalk and Magic Barrier. But Warcryers have no emergency healing like the good old Battle Heal of the Prophet, and Warcryers really need a large party to be really effective, while a prophet also shines in small parties. Last not least warcryers need a lot of levels to max their buffs, while prophets have all the good stuff much earlier.

## Fun Facts

An interesting property of the prophet is that, after level 56, the only thing which becomes still better are the spells Bless the Body, Bless the Soul, and the Resist Element stuff. All other buffs are already maxed. That's why a lot of people only use them as buffer who just sits and buffs at the hunting place of the party.
The important Beserker Spirit buff is often called Zerk in online discussions.
Prophets are not the only class who get the skill to wear heavy armor, Warcryersy and overlords get it too. With heavy armor mastery they get pdef and casting speed bonuses.
# Lineage 2/The Player Character (PC) Classes & Character Guides/Spellhowler

Spellhowler (SH) are offensive spellcasters (nukers) of the darkelves. They wear Robes and can use any weapon, even if they usually prefer those with high M.Atk.
This class specializes into wind and dark magic.

## Key Skills

- TO DO -

## Development

- TO DO -

## Equipment

In general, anything that gives the SH casting speed is usually a good idea. Casting speed means your chance of getting interrupted is much lower, and its a huge advantage in PvP.
There are a lot of options for equipment of the Spellhowler, so I will just present the most popular. On c-grade one would want to combine the Karmian Robe Set with the Ghoul Staff, SA Mana Up, or a Homunculus Sword, SA Acumen, or the Sword of Whispering Death, SA Magic Power. If you really want to use the Demon Robe set instead, getting a +4 Con, -4 Str Symbol might be a good idea. On b-grade the Avadon or Zubei Robe is combined with the Staff of Evil Spirit (no good SA) or the Homunculus Sword with SA Acumen. On a-grade the best combo is probably the Dark Crystal Robe with a Sword of Miracles SA Acumen or SA Magic Power.
The +4 Con, -4 Str Symbol is a must - SHs get absolutely nothing from strength, but are very low on hitpoints and load. Another popular Symbol would be +4 Wit, -4 Men. You can work some of the bad effects of that symbol by wearing, for example, the majestic robe (gives mana regeneration), using a weapon with Mana Up or Conversion (as +4 Wit gives more casting speed than an acumen weapon would give anyway), and getting better jewelry.

## Adventuring

Nukers are loners, and the Spellhowler is even more so than elvish Spellsingers and human Sorcerers, because the later at least have mass sleep spells.
Especially spellsingers can be found to almost go into melee with their spells quite often, because their fastest spells are almost uninterruptible. Spellhowlers however are slow casters, the best strategy for them is to run away until they have some distance, cast their spell, then continue running away. The Slow spell is a very important tool for the spellhowler, as are speed potions.
During soloplay, the spellhowler usually battles to use up his Manapool as slowly as possible. This can be done by casting the Body to Mind spell multiple times between the wind attacks, then combining them with the Vampiric Claw attack.
Dark magic is very strong, but some mobs are very resistant, and wind attacks tend to be cheaper, at least in the beginning. Also, there are no dark mass attacks.

## Fun Facts

Someone placed a detailed plan how to level a spellhowler up to level 20 here, this has been moved to the right place: Dark Mystic.