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ALGEBRA OF MUSICAL TEXT

Level of difficulty Medium
Reading time 5 min
Views 181

Sergey Pshenichnikov, Tatiana Sotnikova

ALGEBRA OF MUSICAL TEXT

Sergey Pshenichnikov, Tatiana Sotnikova

Trio Sapiens

Musical text can be represented using matrix units, like the description of verbal texts and other symbolic sequences. In the future, mathematical recognition, and creation of musical sense with substantive justification for intermediate calculations (as opposed to AI) may become possible.

Sound has four properties: pitch, duration, volume, and timbre. Timbre is not considered yet. The dictionary of the algebra of musical texts is built on the basis of musical notation for the piano.

The duration here, for the sake of brevity of the first presentation, is considered as «absolute». «Relative» is not considered, although intervals are very well studied, and their features will be needed to categorize composers.

The complexity of the musical text for the application of mathematics is explained by the desire to simplify the reading of musical notes by musicians and to minimize the use of lower and upper additional lines.

To apply text algebra to musical symbolic sequences there is no need to use a five-line staff. What is useful and familiar to musicians is «unbearably harmful» for the use of algebra. It seems advisable to use a one-line staff. In this case, the musical text becomes like the verbal text.

To solve the problem, you need to find a transformation of the canonical musical text into a «thread». And as always, for a new application of algebra, correct coordination of the subject area is necessary. In this case, each used musical notation and symbol of modern musical notation must be assigned its own serial number (natural number).

Instead of a sign, you can use the names of each note symbol - then it will be a verbal notation of musical texts written in one line «thread»).

Since the musical scale is completely represented by piano keys, the first section in height of the dictionary of musical texts consists of 88 numbered white and black keys (of which 52 are white). This eliminates the need for an octave division of the scale, octave transfer signs, keys, five alteration signs (key and random), diatonic and chromatic semitones.

All notes of the scale became fundamental in algebraic musical notation. There is an order of magnitude more of them of them than the main stages of Guido Aretinsky, but the alteration signs and names of octaves disappeared, the use of which made musical texts algebraically incompatible with verbal texts. Numbers from 1 to 88 in algebraic notation constitute a fragment of the pitch dictionary for the «thread» one-line staff.

Numbering (coordination) of notes is needed to become in the future indices of mathematical objects (matrix units), which will replace the signs of notes or their names. These matrix units are binary generalizations of integers (hyperbinary numbers). The operation of division with remainder is defined for them, as for integers. The operation will allow you to divide musical texts and their f

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Total votes 3: ↑3 and ↓0 +3
Comments 0

Import chat history to Telegram (приглашение)

Level of difficulty Medium
Reading time 3 min
Views 1.3K
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I'm seeking anyone who is skilled enough to develop a simple Python script using TDLib, Telegram API, and JSON manipulation to make it possible to perform simple tasks listed below:

1. Import Telegram chat JSON backup back to Telegram similar to what these scripts are doing github.com/alexlyzhov/telegram-import
github.com/Suberbia/UltimateChatRestorer
github.com/mygrexit/UltimateChatRestorerForGroupchats
but for any chat (not only to «saved messages») including group chats (not only 1 to 1 chats) and improve the code to make it work faster, more reliable, write log file, allow continuing from the stop point in case of errors and keep all the original chat data including formatting and everything that telegram can handle.
Some kinda combine all the script in one universal, flexible, high quality tool.
The most important aspect of the whole task is that the imported messages have to keep not only the formatting, but its original date and time when they were actually sent. Like it is done in the original telegram tool for importing history from some other apps — telegram.org/blog/move-history

2. Make it very simple to use. Perfect solution will be: Download, put the script next to JSON backup and run it in the interactive mode or with some specific options. Let the script ask for all the credentials and briefly explain where to get them. If possible, keep all the job on one device with no need of transferring the WA format zip file to the phone for importing. If not possible, make it an android app which will get the JSON, process it and feed the result to the Telegram app for import.

This is the basic I'm going to pay for.
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Total votes 6: ↑3 and ↓3 0
Comments 2

Why x^0 = 1 visually

Reading time 3 min
Views 1.1K

The traditional definition for the operation of exponentiation to a natural power (or a positive integer) had introduced approximately as follows:

Exponentiation is an arithmetic operation originally defined as the result of multiple multiplications a number by itself.

But the more precise formulation is still different:

Raising a number X to an integer power N is an arithmetic operation defined as the result of multiple [N by mod times] multiplications or divisions one by number X.

Let's figure it out under the cut! >>
Total votes 5: ↑5 and ↓0 +5
Comments 0

The Collatz conjecture is the greatest math trick of all time

Reading time 4 min
Views 3K

On the Internet and in non-fiction literature you can often find various mathematical tricks. The Collatz conjecture leaves all such tricks behind. At first glance, it may seem like some kind of a trick with a catch. However, there is no catch. You think of a number and repeat one of two arithmetic operations for it several times. Surprisingly, the result of these actions will always be the same. Or, may be not always?

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Total votes 7: ↑7 and ↓0 +7
Comments 2

Russian AI Cup 2020 — a new strategy game for developers

Reading time 5 min
Views 2.4K


This year, many processes transformed, with traditions and habits being modified. The rhythm of life has changed, and there's more uncertainty and strain. But IT person's soul wants diversity, and many developers have asked us if annual Russian AI Cup will be held this year. Is there going to be an announcement? What is the main theme of the upcoming championship? Should I take a vacation?

Though some changes are expected, it will be held in keeping with the best traditions. In the run-up, we will announce one of today's largest online AI programming championships — Russian AI Cup. We invite you to make history!
Total votes 15: ↑15 and ↓0 +15
Comments 0

СodeSide. The new game for Russian AI Cup

Reading time 3 min
Views 2.4K


The AI Cup community and Mail.ru Group in collaboration with Codeforces.com invite you to the real battle! Get ready for the sleepless nights and calloused hands — take part in Russian AI Cup, which is one of the most challenging and vivid artificial intelligence programming competitions in the world. Believe us, managers of this madness did their best to create the game you'd want to play.


To become part of the competition, you need Internet access, computer, creativity, and enthusiasm for being a part of this extraordinary Cup. By the way, you might need some coffee. Welcome!

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Total votes 33: ↑33 and ↓0 +33
Comments 0

How to quickly prepare for a job interview with questions on algorithms and technologies

Reading time 6 min
Views 3K
Greetings to all readers of Habr! My name is Yuriy, I have been teaching high technologies, Oracle, Microsoft and others for more than 20 years, as well as creating, developing and supporting loaded information systems for various business customers. Today I would like to tell you about the current direction: interviews on data processing technologies. The Russian variant of this post you can find here.

It doesn't really make sense for an employer to ask the applicant about traditional programming technologies. That is why I'm going to tell you how to prepare for an interview in only one narrow area related to information processing languages, namely, the processing of long integers(long arithmetic) and the identification of information properties of real world objects, which are described in long integers.
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Total votes 8: ↑6 and ↓2 +4
Comments 0

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