Capability of the alphabet

Содержание и основные понятия

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Alterna · Chapter 10 · page 10.1
Capability of the alphabet
The power of the alphabet, the Hartley I formula = log2(N), the information volume of the text, is all from the GEF/OPF with interactive tasks.
Alphabet
- The final set of characters for the text.
Capability of the alphabet
Each symbol carries a certain amount of information calculated by the Hartley formula.
GEF
PIF
OGE No. 1-4
EEG No. 4
01
What's an alphabet?
Definition of the alphabet and its capacity under GEF
GEF
Definition for GEF
Alphabet
– The final set of characters (letters, numerals, punctuation signs, etc.) used in the recording of textual information.
Capability of alphabet ( < A > or N)
is the number of different symbols that form the alphabet.
Examples of alphabets
Alphabet
Symbols
Power N
Bibular
0, 1
2
Eight
0, 1, 2, 3, 4, 5, 6, 7
8
Decimal
0, 1, 2, ..., 9
10
Latin (A-Z)
26 letters
26
Russian
33 letters + space + puncture signs
~44
DNA
A, C, G, T
4
Morse code
dash, point
2
ASCII
Latin letters, figures, symbols
128 or 256
Unicode
All World Symbols
65 536+
Alphabet and its power
ALPHAVIT
Symbol Set
EFFECTIVENESS N
Number of symbols
SIMVOLA WES i
Information in bits
02
Hartley's formula
The connection between alphabet power and symbol information weight
GEF
OGE No. 3.4
Hartley's formula
There is a connection between the power of alphabet N and the information weight of symbol i:
N = 2
i
или
i = log
2
(N)
where:
N
- Capability of alphabet (number of symbols)
i
- information weight of one symbol (in bits)
Base 2 logarithm
log2(N) is a measure of the degree to which 2 is needed to obtain N. For example: log2(8) = 3, because 23 = 8. If N is not the exact degree of the two, the result will be fractional: log 2 (10) ~ 3.32 bits.
Examples of calculations
Alphabet 2 Symbols
i = log₂(2) =
1 bit
Alphabet 8 Symbols
i = log₂(8) =
3 bits
Alphabet 256 characters
i = log₂(256) =
8 bits = 1 byte
Two steps and weight of information
N (power)
2^i
i (beat)
Example
2
2¹
1
Bibular
4
2²
2
DNA (A,C,G,T)
8
2³
3
Eight
64
2⁶
6
ASCII (expanded)
256
2⁸
8
1 byte per symbol
03
Information volume of text
How to calculate the volume of text in bits and bytes
GEF
OGE No. 3.4
EEG No. 4
Information volume formula
If the alphabet is known and the number of characters in the text is known, you can compute its volume:
I = n × log₂(N)
бит
where:
I
- Information volume (bats)
n
— Number of characters in the text
N
- Power of alphabet
log₂(N)
- information weight of one symbol (in bits)
Example of meeting the objective of the EEG
Objective:
The text is written in an alphabet of 64 characters. In the text of 128 characters. What is the volume of the text in the bits?
Решение:
1. Находим вес символа: i = log₂(64) = 6 бит
2. Вычисляем объём: I = 128 × 6 =
768 бит
3. Переводим в байты: 768 / 8 =
96 байт
🖩
Information volume calculator
Enter the parameters and receive the exact logarithm text.
Number of characters n:
Power of alphabet N:
04
OGE/EGB task bank
10 questions from the task bank by accident
OGE No. 3.4
EEG No. 4
📝
Task bank (10 questions)
Do the task. Choose the answer or enter the number.
05
Mini-test: alphabet power
Five random questions from Bank 40.
0 / 500 XP
0 / 5
Press "Start Quest" for starters.