markov.1

.TH MARKOV 1 2024-06-13

.SH NAME
markov \- Markov algorithms interpreter and their largest library

.SH SYNOPSIS
.B markov
[\fB\-V\fP|\fB\--version\fP]
[\fB\-u\fP|\fB\--usage\fP]
[\fB\-?\fP|\fB\-h\fP|\fB\--help\fP]
[\fB\-rc\fP|\fB\--reset-config\fP]
.br
.B markov
[\fB\-nc\fP|\fB\--no-colors\fP]
\fIalgorithm\-file\fP ...
.br
.B markov
[\fB\-nc\fP|\fB\--no-colors\fP]
\fB\-s\fP|\fB\--sequence\fP
\fIalgorithm-sequence\-file\fP ...

.SH DESCRIPTION
Markov algorithms is a turing-complete string rewriting system used in theoretical and educational purposes.
.br
Hereafter, the description relates to the Markov algorithms alteration implemented in this software.

A \fIword\fP is defined as a finite sequence of alphanumericals (i. e. A-Z, a-z and 0-9).
.br
An \fIempty word\fP is defined as a word with no alphanumericals. An empty word is denoted by ^.
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A word \fBS\fP is said to be a \fIsubword\fP of a word \fBW\fP, if \fBW = XSY\fP. For any word \fBW\fP, \fBW = ^W = W^ = ^W^\fP.

A \fIrule\fP is defined as two words separated with either space-dot-space or space-comma-space.
.br
The first one is called a \fIterminal rule\fP. The second one is called \fInon-terminal rule\fP.
.br
An \fIexecution result of a rule\fP \fBL . R\fP or \fBL , R\fP on the word \fBW\fP is defined as a word \fBW\fP, in which the very first, leftmost subword \fBL\fP is substituted with \fBR\fP. If an execution result of a rule \fBL . R\fP or \fBL , R\fP on a certain word \fBW\fP is equal to the \fBW\fP itself (i. e., if \fBL\fP is not a subword of \fBW\fP), it is said that this execution rule is \fIunworkable\fP on word \fBW\fP.

A \fIMarkov algorithm\fP is a finite list of rules, one per line. Its execution on word \fBW\fP is described as follows:
.RS
1. If each rule is unworkable on word \fBW\fP, the word \fBW\fP is the result of the current Markov algorithm execution.
.br
2. If at least one rule is not unworkable on word \fBW\fP, execute the very first of them on word \fBW\fP.
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3. If an executed rule was terminal, its result is also the result of the current Markov algorithm execution.
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4. If an executed rule was non-terminal, process its result as a word \fBW\fP.

            ┌───────────────┬───────────────────────┬───────── Out1
.br
            │ 2             │ 2                     │ 2
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   In ┏━━━━━┷━━━━━┓ 1 ┏━━━━━┷━━━━━┓ 1       1 ┏━━━━━┷━━━━━┓ 1
.br
─┬────┨  L1 x R1  ┠───┨  L2 x R2  ┠────***────┨  Ln x Rn  ┠─── Out2
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 │    ┗━━━━━┯━━━━━┛   ┗━━━━━┯━━━━━┛           ┗━━━━━┯━━━━━┛
.br
 │          │ 3             │ 3                     │ 3
.br
 └──────────┴───────────────┴───────────────────────┘

.SH OPTIONS
.RE
\fB\-V\fP, \fB\--version\fP
.RS
Display a version message and exit immediately.

.RE
\fB\-u\fP, \fB\--usage\fP
.RS
Display a usage message and exit immediately.

.RE
\fB\-?\fP, \fB\-h\fP, \fB\--help\fP
.RS
Display a help message and exit immediately.

.RE
\fB\-nc\fP, \fB\--no-colors\fP
.RS
Disable font colors and styles.
.br
They are disabled whether or not this option is set, if any of these are true:
.RS
a) \fBmarkov\fP output is not directed into the terminal
.br
b) user \fBecho\fP can not process escape-sequences

.RE
.RE
\fB\-s\fP, \fB\--sequence\fP
.RS
Process each passed file as an algorithm sequence rather than an algorithm.

.SH CONFIGURATION
.RE
The configuration allows each following option to be set or unset if not passed as an argument:
.RS
\fB\--no-colors\fP
.br
\fB\--sequence\fP

.RE
Configuration is done by editing the configuration file.
.br
The absolute path of the configuration file is \fB~/.config/markov/markov.conf\fP.

The configuration file is set automatically once \fBmarkov\fP is launched, if any of these are true:
.RS
a) option \fB\-rc\fP|\fB\--reset-config\fP is passed
.br
b) the configuration file is empty
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c) the configuration file is not present
.br

.RE
The data of the configuration file that is thus set is \fBNO_COLORS=0; SEQUENCE=0\fP.
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With such configuration file data, each corresponding option is unset if not passed as an argument.
.br
\fB1\fP written respectively in the configuration file will give the opposite result for an option.

.SH FILES
\fBmarkov\fP is provided with the library of Markov algorithms and their sequences.
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These are located at \fB~/.config/markov/library/\fP and are as follows:

├── algorithms
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│   ├── binary_to_preunary
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│   ├── decimal_to_dekimal
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│   ├── dekimal_to_decimal
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│   ├── dekimal_to_unary
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│   ├── division
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│   ├── factorial
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│   ├── greatest_common_divisor
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│   ├── lenght
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│   ├── multiplication
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│   ├── neumann
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│   ├── power
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│   ├── prefix
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│   ├── substraction
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│   ├── suffix
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│   ├── summation
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│   ├── unary_compare
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│   └── unary_to_dekimal
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└── sequences
    ├── binary_to_decimal
    ├── compare
    ├── division
    ├── factorial
    ├── greatest_common_divisor
    ├── multiplication
    ├── power
    ├── substraction
    └── summation

For each sequence, except of \fBbinary_to_decimal\fP and \fBfactorial\fP, an input word is two decimal numbers separated with \fBa\fP. 

.SH EXAMPLES
\fBmarkov -s binary_to_decimal\fP
.br
Input word: 11101010110101
.br
15029

\fBmarkov -s compare\fP
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Input word: 23687a6472
.br
>

\fBmarkov -s division\fP
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Input word: 2837a234
.br
12

\fBmarkov -s factorial\fP
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Input word: 7
.br
5040

\fBmarkov -s power\fP
.br
Input word: 2a13
8192

.SH AUTHOR
Ruslan Abbas Al Faraui <github.com/faraui>.

.SH SEE ALSO
\fBgrep\fP(1), \fBsed\fP(1), \fBtr\fP(1), \fBsort\fP(1), \fBmawk\fP(1), \fBgawk\fP(1).