In block diagrams, input and output operations are indicated. Algorithm flowcharts - educational and scientific activities of Vladimir Viktorovich Anisimov

To visualize the stages of any process, it is convenient to use flowcharts. They allow you to present a logical chain in the form of separate graphic elements combined in the desired order.

A great way to quickly make a flowchart is to use special online programs. Let's look at how they work and what features they have using the example of three Russian-language editors.

How to draw a beautiful diagram inCanva

We have already talked about the Canva website many times in our articles. This one is ideal for creating infographics, presentations, posters, outdoor advertising, etc. Today we’ll talk about how Canva will help you build a flowchart online.

To begin with, it’s worth saying that of all the services that we will consider today, this is the only resource that allows you not only to create a clear and structured diagram, but also to design it beautifully. The site is intended more for designers than for mathematicians or programmers, so if you need, for example, to create a colorful diagram for presenting a project or marketing plan, then Canva is definitely the best assistant.

First, choose the template you like among dozens of different options.

Conveniently, most of the layouts here are provided for free.

You can customize absolutely everything here: from the font of the inscriptions to the structure of the image

In addition, it is possible to add beautiful diagrams

This section also has a function for inserting the created image onto your Internet resource. You just need to copy the code snippet with the diagram and paste it into your blog or website

When work on the flowchart is completed, click “Download”.

Selecting the file format

One of the big advantages of using Canva is that the image is ultimately saved without any watermarks.

Convenient construction of logical chains withDraw. io

Another free online service worthy of your consideration is Draw.io. It is considered one of the most famous sites for creating diagrams, diagrams, graphs and structures. Here, just like in Canva, it is possible to connect a Russian-language interface, which greatly simplifies the process.

Before starting work, we are asked to choose a place to save the finished result, as well as decide on the layout.

Thanks to Draw.io for the convenient structuring of the templates - they are all divided into categories, which allows you to choose the right option as quickly as possible

Let's move on to editing. To change an element, simply click on it with the mouse, after which the style, text and layout characteristics are displayed on the right.

Compared to the previous service, the settings here seem a little primitive, but nevertheless all the necessary parameters are present

To replace a shape, select a suitable object in the left panel and drag it to the desired location. It’s convenient that when you move elements, all the arrows attached to them automatically change their position.

It is also possible to insert a ready-made diagram or other image into the document by importing it from a computer, cloud storage or online resource

To save the result, click “File” - “Save As”, after which we are offered the following options:

Google Drive;
OneDrive;
Dropbox;
GitHub;
Trello;
computer;
browser.

The finished file is downloaded in .xml format.

Google chart – a powerful tool for developers

Finally, our list of recommendations ends with the Google chart API. It is a library of code snippets that, when embedded, appear on your website to create beautiful charts, graphs, structures, tables, etc.

Select the desired category

Using the example, we see what the diagram will look like if we do not change the main essence of the code

After copying and pasting into our website, we need to enter the appropriate data instead of the ones given in the example. This is not difficult, given that the code has many useful comments and clarifications.

For experienced programmers, the Google chart API will become an indispensable assistant, because it offers a wide range of additional tools for effective visualizations. If you are not a very confident developer, you can use the standard options - they also look quite decent.

All the programs we reviewed are completely different, so it is impossible to single out the most convenient one. It all depends on your goals and wishes. If you need to get a beautiful graphic product, then no site can do it better than Canva. If you need a minimalistic diagram without any special frills, Draw.io will come to the rescue. If you want to write code for your chart, use the Google chart API.

If you need to create a flowchart without using the Internet, you can do it in Word 2016. The process will not be as convenient and fast as in the case of online programs, because There are no blanks or templates here. All elements and connections between them will have to be drawn from scratch, so be patient.

Flowcharts are diagrams that show the steps of a process. Simple flowcharts are easy to create, and the simplicity and clarity of the shapes make them easy to understand.

Note. You can also automatically create a simple flowchart from your data using the Data Visualizer in Visio Online (Plan 2). For more information, see Create diagrams using Data Visualizer.

The Simple Flowchart template in Visio contains shapes that you can use to visually represent a variety of processes. It is especially useful for displaying simple business processes, such as the proposal development process shown in the figure below.

In addition to the Simple Flowchart template, Visio offers a variety of more specific diagram templates, such as data flow diagrams, timelines, and software models.

Creating a Flowchart

Launch the Visio application.

Double-click the icon Simple block diagram.

To connect elements of a flowchart, hover your mouse over the first shape, and click the arrow pointing to the shape you want to connect to. If the second shape is not next to the first, you need to drag the small arrow to the center of the second shape.

To change the direction of the connector arrow, select the connection, and then on the tab in the group Shape styles click item Line Arrows and select the desired direction and type of arrow.

Automatic alignment and spacing

Press CTRL+A to select all objects on the page.

On the tab home in Group Ordering click the button Position and select Auto-alignment and spacing.

If this does not produce the desired result, cancel it by pressing CTRL+Z and try other button menu options Alignment And Position.

What do flowcharts represent?

When opening a template Simple block diagram a set of elements opens Simple flowchart shapes. Each figure in this set represents one or another stage of the process. But the figures do not have any universal meaning; their meaning is determined by the creators and users of flowcharts. Most flowcharts use three or four types of shapes, and this range is expanded only as specific needs arise.

At the same time, the names of shapes in Visio indicate their use. The most common shapes are described below.

What do flowcharts represent?

Visio 2010 has many other specialized sets of stencils and shapes that you can use in a flowchart. For more information about other shapes, see the article.

Note: Can't find the shape you're looking for? For more information about how to find other shapes, see Organize and find shapes using the Shapes window.

Creating a Flowchart

Open the tab File.

Tab File not displayed

If the tab File is not displayed, proceed to the next step in the procedure.

Select a team Create and point Block diagram and then in the list Available templates select element Simple block diagram.

Click the button Create.

For each step in the process you're documenting, drag the appropriate flowchart shape into your document.

Note: For information about using shapes to represent each step in a process, see .

By default rectangular

Straight Connectors

To return to normal editing on a tab home in Group Service click the button Pointer.

To add text for a shape or connector, select it and enter text. When you've finished entering text, click in a blank area of the page.

To change the direction of the connector arrow, select the connection, and then in the group, click the arrow to the right of the label Line, hover over the item Arrows and select the desired direction.

Printing a Large Flowchart

Before you start printing, you need to make sure that the drawing page displayed in Visio contains the entire flowchart. Any shapes that extend beyond the page in Visio will not print.

To print a large flowchart, do the following:

What do flowcharts represent?

When you open the Simple Flowchart template, the Simple Flowchart Shapes stencil also opens. Each shape in the set of elements corresponds to a specific step in the process.

Of the shapes included in the Simple Flowchart Shapes stencil, only a few are widely used. These figures are described below. For more information about other shapes, see the link (Less popular flowchart shapes) at the end of this section.

Less Popular Flowchart Shapes

Dynamic connecting line. This connecting line bypasses the figures lying in its path.

This is a connecting line with customizable curvature.

This is a text box with a border that resizes based on the amount of text you enter. The width can be set by dragging the sides of the shape. This figure does not represent a step in a process, but is useful for labeling a flowchart.

Note. This is a box in square brackets that changes in size depending on the amount of text you enter. The width can be set by dragging the sides of the shape. Like the Auto-Height Field, this figure does not represent a step in the process. Use it to add notes to flowchart shapes.

Manual input. This is the stage where a person provides information to the process.

Manual operation. This is a step that must be completed by a person.

Internal storage. This shape represents data that is stored on a computer.

Direct data. This figure represents data that is stored in such a way that each individual record can be directly accessed. This corresponds to the way data is stored on a computer's hard drive.

Serial data. This shape represents data that is stored sequentially (for example, data on magnetic tape). Such data can only be read sequentially. For example, to access record 7, you must first view records 1–6.

Map and paper tape. This figure represents a punched card or paper tape. Early computer systems used punched cards and paper tapes to write and read data and to store and run programs.

Display. This shape represents the data displayed to the user (usually on a computer screen).

Preparation. This figure represents the initialization of variables in preparation for executing a procedure.

Parallel mode. This figure shows where two different processes can be running simultaneously.

Cycle limit. This figure shows the maximum number of times a cycle can be repeated before moving on to the next step.

Transfer of control. This figure denotes a stage at which, if certain conditions are met, a transition occurs not to the next, but to another stage.

Creating a Flowchart

On the menu File Create, then to point Block diagram and select Simple block diagram.

For each step in the process you're documenting, drag the appropriate flowchart shape into your document.

Connect the shapes in the flowchart using one of the following methods.

Connecting two shapes to each other

Connecting one shape to several using a single connection point

By default rectangular connecting lines, and connecting a point on a shape to three other shapes looks like the picture below.

To have connecting lines start directly from the center point of the first shape and lead to points on all other shapes, you must specify Straight Connectors, as shown in the figure below.

On the toolbar Standard click tool Pointer to return to normal editing mode.

To add text for a shape or connector, select it and enter text. When you've finished entering text, click in a blank area of the page.

To change the direction of the connector line, in the menu, hover your mouse pointer over Operations and select Twist the ends.

Printing Large Block Diagrams

The easiest way to print a flowchart that is larger than paper is to print it on several sheets of paper and then glue them together.

Before you start printing, you need to make sure that the drawing page displayed in Visio contains the entire flowchart. Any shapes that extend beyond the page in Visio will not print. To check whether the flowchart fits on the document page, use the preview in the dialog box Page settings(menu File, paragraph Page settings, tab Printing settings).

1. Block diagram. which is too large for the Visio drawing page.

2. A flowchart that is placed on a Visio drawing page.

Change the Visio drawing page size to fit the flowchart size

When a flowchart is open, in the menu File select item Page settings.

Open the tab Page size.

On the tab Page size click .

To see how the flowchart will look when printed, go to the menu File select item Preview. The figure below shows the flowchart that will be printed on four letter-size sheets.

Printing large flowcharts on multiple sheets of paper

On the menu File select item Page settings.

On the tab Printing settings in field Paper in the printer Select the paper size you want if it is not already selected. Don't press the button OK.

Open the tab Page size and click Resize by content. The preview window now shows the difference between the new page and the paper in the printer.

Click the button OK.

On the menu File select item Preview to see how the flowchart will look when printed.

Note: Shaded margins may appear between pages. These correspond to the areas that will be printed on both sheets. This allows you to glue the sheets together so that there are no empty spaces on the block diagram.

Once printing is complete, you can trim the margins, arrange the pages properly, and glue them together.

A flowchart is a graphical model that describes processes or algorithms, where the steps are blocks of various shapes, and they are connected by lines. And these lines show the direction of the sequence. How the block diagram should be executed is regulated by the standard. And it serves so that a programmer or a person who does not have knowledge in this area can clearly see how a program or process works. Flowcharts are often created by programming professionals.

Why does a programmer need a flowchart?

FlowChart notation is the fastest, most versatile and accessible method by which a programmer can explain to a non-specialist how any process is performed or a program works. A block diagram also represents documentation for any program. If a programmer needs to explain how a simple utility or small code works, he can clearly demonstrate this using a regular graphics editor. But if the program is complex, its code consists of many modules and lines, a simple editor will not work. In this case, programmers use professional solutions and build a flowchart based on the source code.

Programs and online services for constructing block diagrams

You can use special programs that run on your computer, or services that offer real-time construction of any circuit using Pascal, Delphi, and even C++. Experienced programmers prefer to use only computer programs.

Services that are provided for online process mapping often do not support the necessary requirements and therefore cannot guarantee correct operation. For example:

A number of programming language commands are not supported and, therefore, the sequence diagram of actions is not constructed correctly.
The graphs showing the sequence of operations are poorly drawn.
The online service often does not provide the opportunity to save the flowchart in the required format.
And these are not all the disadvantages of such services.

Special computer applications handle the task of constructing flowcharts much more professionally. Well, for those who do not want to install programs on their computer, we recommend using the software interface for creating charts and graphs Chart API from Google.

FCeditor is a convenient application that supports the programming languages C++ (.cs file), Delphi, Pascal (.pas file). If you need to edit a code file in this program, you must import it first. When FCeditor parses the imported .pas or .cs file, it will display a class tree on the left, a tab will appear in the panel, and in it will be the program code and diagrams.

Important note! You can export the constructed graph or diagram to any format: from jpeg and tiff to png and bmp. The program has Russian-language support and a simple user interface.

Another simple program with a minimalist design but wide functionality. The user interface, similar to the previous program, is simple and convenient even for non-professionals. In the main window you will see three fields. In the first field, the code is presented in a tree form, in the second - the text itself, and in the third, largest, you will see a constructed diagram or graph. This application is convenient to use because of the backlight. Elements of the code, tree structure, and diagram are not only highlighted, but also collapsed.

The diagram created in the Autoflowchart program can be exported not only to graphic format, but also to xml files. This program is also a convenient code editor. Anything you edit in code is instantly displayed in the diagram. Autoflowchart supports any programming language.

Code Visual to Flowchart version 6.0 is the most powerful computer program used by professionals to create charts and graphs. It is distinguished by extensive functionality and the ability to build an accurate circuit. Despite the sophisticated functionality and capabilities, the program has a convenient user interface. In the main window you will see three fields. There are two tabs on the left: one shows the structure of the project, the other shows the structure of classes. In the center of the main window you will see the program code, and on the right - a diagram of the code segment.

You can export the constructed diagram into only two formats: png and bmp.

Important note! All of these programs are great solutions to help you create clear, standard-compliant flowcharts. But to use each of the programs discussed above, you will have to pay. The trial version provides only a small part of the functionality and is therefore suitable for evaluation purposes only.

Often, application development begins with building a flowchart. Before you create a program code, you need to think it through and draw up a diagram of the sequence of actions. And this is the scheme on the basis of which the programmer then writes code.

For those who are accustomed to using online services, we recommend two proven ones - Chart from Google and Draw.io

Draw.io is a convenient service in which you can build and edit flowcharts. Its extensive functionality, user-friendly interface and package of tools allow you to edit, format and modify blocks, creating them according to a standard scheme or an individual one. You can also use external images when creating a diagram. The finished diagram can be saved in graphic, vector formats, or as a document on cloud storage, or downloaded to your computer.

Draw.io will appeal to novice programmers for its rich functionality and ease of use. And what’s important is that you can use it absolutely free.

Google's Chart API perfectly visualizes any code and creates graphs, charts and charts. An extensive toolkit is represented by plug-in libraries, with the help of which high-quality graphs and diagrams are created. Google's service has a huge variety of schemes in its functionality, with the help of which not only programs are created, but also websites and documents.

To use this powerful online service, you only need to read the detailed instructions and have minimal knowledge. How to properly use all the service library tools from Google is shown in the document package.

Google's Chart API is a great tool for professional programmers.

STATE STANDARD OF THE USSR UNION

UNIFIED SOFTWARE DOCUMENTATION SYSTEM

DIAGRAMS OF ALGORITHMS, PROGRAMS, DATA AND SYSTEMS

CONVENTIONS AND IMPLEMENTATION RULES

GOST 19.701-90
(ISO 5807-85)

USSR STATE COMMITTEE FOR PRODUCT QUALITY MANAGEMENT AND STANDARDS

STATE STANDARD OF THE USSR UNION

Date of introduction 01.01.92

This standard applies to conventions (symbols) in diagrams of algorithms, programs, data and systems and establishes rules for the execution of diagrams used to display various types of data processing problems and means for solving them.

The standard does not apply to the form of entries and symbols placed within or adjacent to symbols that serve to clarify the functions they perform.

The requirements of the standard are mandatory.

1. GENERAL PROVISIONS

1.1. Diagrams of algorithms, programs, data and systems (hereinafter referred to as diagrams) consist of symbols with a given meaning, short explanatory text and connecting lines.

1.2. Schemas can be used at various levels of detail, with the number of levels depending on the size and complexity of the data processing problem. The level of detail should be such that the various parts and the relationships between them are understood as a whole.

1.3. This standard defines symbols for use in data processing documentation and provides guidance on conventions for use in:

1) data schemas;

2) program diagrams;

3) schemes of system operation;

4) schemes of program interaction;

5) system resource diagrams.

1.4. The standard uses the following concepts:

1) basic symbol - a symbol used in cases where the exact type (type) of a process or storage medium is unknown or there is no need to describe the actual storage medium;

2) specific symbol - a symbol used in cases where the exact type (kind) of a process or storage medium is known or when it is necessary to describe the actual storage medium;

3) diagram - a graphical representation of the definition, analysis or method of solving a problem, in which symbols are used to display operations, data, flow, equipment, etc.

2. DESCRIPTION OF THE CIRCUIT

2.1. Data Schema

2.1.1. Data schemas represent the path of data in solving problems and define the processing steps as well as the various storage media used.

2.1.2. The data schema consists of:

1) data symbols (data symbols can also indicate the type of storage medium);

2) symbols of the process that should be performed on the data (process symbols can also indicate functions performed by the computer);

3) line symbols indicating data flows between processes and (or) storage media;

2.1.3. Data symbols precede and follow process symbols. The data schema begins and ends with data characters (except for special characters, ).

2.2. Program outline

2.2.1. Program diagrams display the sequence of operations in a program.

2.2.2. The program scheme consists of:

1) process symbols indicating the actual data processing operations (including symbols defining the path that should be followed, taking into account logical conditions);

2) linear symbols indicating control flow;

3) special symbols used to make the diagram easier to write and read.

2.3. System operation diagram

2.3.1. System operation diagrams depict the control of operations and the flow of data in the system.

2.3.2. The system operation scheme consists of:

1) data symbols indicating the presence of data (data symbols may also indicate the type of data carrier);

2) process symbols, indicating the operations that should be performed on the data, and also defining the logical path that should be followed;

3) linear symbols indicating data flows between processes and (or) storage media, as well as control flow between processes;

4) special symbols used to make the flowchart easier to write and read.

2.4. Program interaction diagram

2.4.1. Program interaction diagrams display the path of program activation and interaction with the corresponding data. Each program in the program interaction diagram is shown only once (in the system operation diagram, a program can be displayed in more than one control flow).

2.4.2. The program interaction scheme consists of:

1) data symbols indicating the presence of data;

2) process symbols indicating the operations that should be performed on the data;

3) linear symbols depicting the flow between processes and data, as well as the initiation of processes;

4) special symbols used to make the diagram easier to write and read.

2.5. System resource diagram

2.5.1. System resource diagrams represent the configuration of data and processing units that is required to solve a task or set of tasks.

2.5.2. The system resource diagram consists of:

1) data symbols displaying the input, output and storage devices of the computer;

2) process symbols representing processors (central processing units, channels, etc.);

3) linear symbols displaying data transfer between I/O devices and processors, as well as transfer of control between processors;

4) special symbols used to make the diagram easier to write and read.

Examples of circuit implementation are given in.

3. DESCRIPTION OF SYMBOLS

3.1. Data symbols

3.1.1. Basic Data Symbols

3.1.1.1. Data

The symbol displays data, the storage medium is not defined.

3.1.1.2. Memorized data

The symbol displays the stored data in a form suitable for processing; the storage medium is not defined.

3.1.2. Specific data characters

3.1.2.1. Random Access Memory

The symbol displays the data stored in the random access memory device.

3.1.2.2. Serial access memory

The symbol represents data stored in a serial access storage device (magnetic tape, magnetic tape cassette, tape cassette).

3.1.2.3. Direct access storage device

The symbol represents data stored in a direct access storage device (magnetic disk, magnetic drum, floppy disk).

3.1.2.4. Document

The symbol displays data presented on the medium in a readable form (machine diagram, document for optical or magnetic reading, microfilm, roll of tape with summary data, data entry forms).

3.1.2.5. Manual input

The symbol displays data entered manually during processing from any type of device (keyboard, switches, buttons, light pen, barcode strips).

3.1.2.6. Map

The symbol displays data presented on a card-like medium (punched cards, magnetic cards, cards with readable tags, cards with a tear-off label, cards with scannable tags).

3.1.2.7. Paper tape

The symbol displays data presented on a medium in the form of a paper tape.

3.1.2.8. Display

The symbol displays data presented in human-readable form on a medium in the form of a display device (visual observation screen, information input indicators).

3.2. Process symbols

3.2.1.Basic process symbols

3.2.1.1. Process

The symbol represents a data processing function of any kind (performing a specific operation or group of operations that results in a change in the value, form, or placement of information, or in determining which of several flow directions to follow).

3.2.2. Process specific symbols

3.2.2.1. Predefined Process

The symbol displays a predefined process consisting of one or more operations or program steps that are defined elsewhere (in a subroutine, module).

3.2.2.2. Manual operation

The symbol represents any process performed by a person.

3.2.2.3. Preparation

The symbol represents the modification of an instruction or group of instructions to affect some subsequent function (setting a switch, modifying an index register, or initializing a program).

3.2.2.4. Solution

The symbol represents a decision or switch-type function that has one input and a number of alternative outputs, one and only one of which can be activated after evaluating the conditions defined within the symbol. The corresponding calculation results can be written adjacent to the lines representing these paths.

3.2.2.5. Parallel activities

The symbol represents the synchronization of two or more parallel operations.

Example.

Note. Processes C, D and E cannot start until process A has completed; similarly, process F must wait for processes B, C, and D to complete, but process C may start and/or complete before process D starts and/or completes, respectively.

3.2.2.6. Loop boundary

The two-part symbol represents the beginning and end of the cycle. Both parts of the symbol have the same identifier. Conditions for initialization, increment, termination, etc. are placed inside the symbol at the beginning or end, depending on the location of the operation that checks the condition.

Example.

3.3. Line symbols

3.3.1.Basic line symbol

3.3.1.1. Line

The symbol represents the flow of data or control.

Directional arrows may be added as needed or to improve readability.

3.3.2.Specific line symbols

3.3.2.1. Transfer of control

The symbol represents a direct transfer of control from one process to another, sometimes with the possibility of a direct return to the initiating process after the initiated process has completed its functions. The type of control transfer must be named within the symbol (eg request, call, event).

3.3.2.2. Link

The symbol displays data transmission over the communication channel.

3.3.2.3. Dotted line

A symbol represents an alternative relationship between two or more symbols. In addition, the symbol is used to outline the annotated area.

Example 1.

When one of a number of alternative outputs is used as an input to a process, or when an output is used as an input to alternative processes, these symbols are connected by dotted lines.

Example 2.

An output used as an input to the next process can be connected to that input using a dotted line.

3.4. Special symbols

3.4.1. Connector

The symbol represents the exit to part of the circuit and the entrance from another part of this circuit and is used to break a line and continue it in another place. Corresponding connector symbols must contain the same unique designator.

3.4.2. Terminator

The symbol represents output to the external environment and input from the external environment (beginning or end of the program diagram, external use, and source or destination of data).

3.4.3.A comment

The symbol is used to add descriptive comments or explanatory notes for the purpose of explanation or notes. The dotted lines in a comment symbol are associated with a corresponding symbol or can outline a group of symbols. The text of comments or notes should be placed near the bounding shape.

Example.

3.4.4. Pass

The symbol (three dots) is used in diagrams to indicate the omission of a symbol or group of symbols in which neither the type nor the number of symbols is specified. The symbol is used only within or between line symbols. It is used mainly in diagrams depicting general solutions with an unknown number of repetitions.

Example.

4 RULES FOR THE APPLICATION OF SYMBOLS AND EXECUTION OF DIAGRAMS

4.1. Rules for using symbols

4.1.1. A symbol is intended to graphically identify the function it represents, regardless of the text within that symbol.

4.1.2. The symbols in the diagram should be evenly spaced. Keep connections to reasonable lengths and keep the number of long lines to a minimum.

4.1.3. Most symbols are designed to allow text to be included within the symbol. The symbol forms specified in this standard are intended to serve as a guide for the symbols actually used. Angles and other parameters that affect the appropriate shape of the symbols should not be changed. Symbols should be the same size if possible.

Characters can be drawn in any orientation, but horizontal orientation is preferred whenever possible. Mirroring the shape of a character denotes the same function, but is not preferred.

4.1.4. The minimum amount of text necessary to understand the function of a given symbol should be placed within the given symbol. Reading text should be written from left to right and top to bottom, regardless of the direction of flow.

Example.

If the amount of text placed inside a symbol exceeds its dimensions, a comment symbol should be used.

If the use of comment symbols could confuse or disrupt the flow of the diagram, the text should be placed on a separate sheet and a cross-reference to the symbol should be provided.

4.1.5. Schemes may use a symbol identifier. This is the identifier associated with a given symbol, which identifies the symbol for reference use in other documentation elements (for example, a program listing). The symbol ID should be located to the left above the symbol.

Example.

4.1.6. Diagrams may use symbol descriptions—any other information, for example to show a special use of a symbol with a cross-reference, or to enhance understanding of a function as part of a diagram. The description of the symbol should be located to the right above the symbol.

Example.

4.1.7. In system diagrams, symbols representing storage media often represent input/output methods. To be used as a reference to documentation, the text on the diagram for symbols representing output methods should be placed to the right above the symbol, and the text for symbols representing input methods should be placed to the right below the symbol.

Example.

4.1.8. Diagrams may use a detailed representation, which is indicated by a bar symbol for process or data. The bar symbol indicates that more detailed information is available elsewhere in the same documentation set.

A stripe symbol is any symbol that has a horizontal line drawn inside it at the top. Between this line and the top line of the symbol is an identifier indicating a detailed representation of that symbol.

The terminator character must be used as the first and last character of the verbose representation. The first terminator character must contain a reference, which is also present in the bar character.

Symbol with stripe Detailed view

4.2. Rules for making connections

4.2.1. Data flows or control flows in diagrams are shown as lines. The flow direction from left to right and from top to bottom is considered standard.

In cases where it is necessary to bring greater clarity to the diagram (for example, when making connections), arrows are used on the lines. If the flow is in a direction other than the standard one, the arrows should indicate that direction.

4.2.2. Intersecting lines should be avoided in diagrams. Intersecting lines have no logical connection with each other, therefore changes in direction at the intersection points are not allowed.

Example.

4.2.3. Two or more incoming lines can be combined into one outgoing line. If two or more lines merge into one line, the location of the merge must be shifted.

Example.

4.2.4. Lines in diagrams should approach the symbol either from the left or from above, and originate either from the right or from below. The lines should be directed towards the center of the symbol.

4.2.5. If necessary, lines in diagrams should be broken to avoid unnecessary intersections or too long lines, and also if the diagram consists of several pages. The connector at the beginning of the break is called the outer connector, and the connector at the end of the break is called the inner connector.

Example.

External connector Internal connector

4.3. Special conventions

4.3.1. Multiple exits

4.3.1.1. Multiple exits from a symbol should be shown:

1) several lines from this symbol to other symbols;

2) one line from a given symbol, which then branches into the corresponding number of lines.

Examples.

4.3.1.2. Each symbol output must be accompanied by corresponding condition values to show the logical path it represents, so that those conditions and corresponding references are identified.

Examples.

4.3.2. Repeating view

4.3.2.1. Instead of a single symbol with associated text, multiple overlapping symbols, each containing descriptive text, may be used (using or generating multiple storage media or files, producing multiple copies of printed reports or punched card formats).

4.3.2.2. When multiple characters represent an ordered set, the ordering must be from front (first) to back (last).

4.3.2.3. Lines can enter or originate from any point on the overlapping symbols, but the requirements must be met. The priority or sequential order of multiple symbols is not changed by the point at which a line enters or departs.

Example.

5. APPLICATION OF SYMBOLS

	Symbol name	Data Schema	Program outline	System operation diagram	Program interaction diagram	System resource diagram
Data symbols
Basic

	Memorized data
Specific
	Random Access Memory
	Sequential Access Memory
	Direct access storage device
	Document
	Manual input

	Paper tape

Algorithm flowchart

An example of a block diagram of an algorithm for calculating the factorial of a number N

Scheme- a graphical representation of a definition, analysis, or method for solving a problem, which uses symbols to display operations, data, flow, equipment, etc. (GOST 19.701-90).

Block diagram- a common type of diagram that describes algorithms or processes, depicting steps in the form of blocks of various shapes, connected by arrows.

Performance Standards

The rules for implementing schemes are determined by the following documents:

For software documentation:

These documents in particular regulate the methods of constructing circuits and the appearance of their elements.

Basic elements of algorithm schemes

Name	Designation	Function
Terminator (start-stop)		The element displays the input from or output from the external environment (the most common use is the beginning and end of the program). The corresponding action is written inside the figure.
Process		Performing one or more operations, processing data of any kind (changing the value of data, presentation form, location). Inside the figure, the operations themselves are written directly, for example, the assignment operation: a = 10b + c*.
Solution		Displays a switch-type decision or function with one input and two or more alternative outputs, of which only one can be selected after evaluating the conditions defined within the element. The entrance to an element is indicated by a line, usually entering the top vertex of the element. If there are two or three exits, then usually each exit is indicated by a line coming out of the remaining vertices (side and bottom). If there are more than three outputs, then they should be shown as one line coming out from the top (usually the bottom) of the element, which then branches. The corresponding calculation results can be written next to the lines representing these paths. Examples of solutions: in the general case - comparison (three outputs: > , < , = ); in programming - conditional statements if(two outputs: true, false) And case(multiple exits).
Predefined Process		The symbol displays the execution of a process consisting of one or more operations, which is defined elsewhere in the program (in a subroutine, module). The name of the process and the data transferred to it are written inside the symbol. For example, in programming - calling a procedure or function.
Data (input Output)		Converting data into a form suitable for processing (input) or displaying the results of processing (output). This symbol does not identify the storage medium (specific symbols are used to indicate the type of storage medium).
Loop boundary		The symbol consists of two parts - respectively, the beginning and end of the cycle - operations performed within the cycle are placed between them. Loop and increment conditions are written inside the loop start or end symbol, depending on the type of loop organization. Often, to depict a cycle in a block diagram, instead of this symbol, a solution symbol is used, indicating the condition in it, and one of the output lines is closed higher in the block diagram (before the operations of the cycle).
Connector		The symbol represents an output to a part of the circuit and an input from another part of that circuit. Used to break a line and continue it in another place (example: splitting a flowchart that does not fit on the sheet). The corresponding connecting symbols must have one (and unique) designation.
A comment		Used to describe a step, process, or group of processes in more detail. The description is placed on the side of the square bracket and is covered along its entire height. The dotted line goes to the element being described, or to a group of elements (the group is highlighted by a closed dotted line). Also, the comment symbol should be used in cases where the amount of text in some other symbol (for example, a process symbol, a data symbol, etc.) exceeds its volume.

Descriptions of other circuit elements can be found in the relevant GOSTs (listed above).

The order of actions is specified by connecting vertices with arcs, which allows us to consider flowcharts not only as a visual interpretation of the algorithm, convenient for human perception, but also as a weighted directed graph. However, not any directed graph composed of vertices of the above types is a correct algorithm. For example, more than one arc cannot extend from an operator vertex. Therefore, in practice, we usually limit ourselves to considering a subclass of graph-schemes of algorithms that satisfy the properties of security, liveness and stability.

Dragon-schemes

Recently, structural, mathematically rigorous block diagrams have appeared, which are called “dragon diagrams”. With the advent of dragon diagrams, flowcharts began to lose their importance, since they are inferior to dragon diagrams in all respects.