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Установка Graphviz и вводное руководство под windows
Поскольку используется дерево решений глубокого обучения, необходимо интуитивно экспортировать файл .dot в виде графа. Итак, вам нужно использовать graphviz.
Адрес для перепечатки: http://blog.csdn.net/lanchunhui/article/details/49472949
- Загрузите и установите переменные среды конфигурации
- intall
- Настроить переменные среды
- проверка
- graph
- digraph
- Сложный пример
Обнаружение хороших инструментов похоже на открытие нового мира. Иногда нам будет любопытно, как сделать такие яркие иллюстрации в бумагах и книгах всех без исключения профессий без умелого использования рисовальных инструментов.
Скачать, установить, настроить переменные среды
intall
Двойной клик msi File, а затем перейдите к следующему (запомните путь установки, путь по умолчанию — C: \ Program Files (x86) \ Graphviz2.38, информация о пути будет использоваться для настройки переменных среды позже), после завершения установки, в меню «Пуск» Windows будет создано сообщение с ярлыком. Ярлык по умолчанию не размещается на рабочем столе. Чтобы
Настроить переменные среды
Добавьте папку bin в каталоге установки graphviz в переменную среды Path:
проверка
Войдите в интерфейс командной строки Windows, введите dot -version , А затем нажмите Enter.Если отображается соответствующая информация о версии graphviz, установка и настройка выполнены успешно.
Используйте команду в окне cmd, чтобы преобразовать точечный файл в графический файл pdf.
Вам нужно ввести преобразованный путь к файлу, иначе вы не знаете, куда идти.
dot -Tpdf D:\mycodes\pythonStudy\python\allDecisionTree.dot -o D:\mycodes\pythonStudy\python\allDecisionTree.pdf
Начало работы с основным рисунком
Откройте редактор graphviz под окнами gvedit , Напишите следующий язык сценариев с точкой и сохраните его как текстовый файл в формате gv. Затем войдите в интерфейс командной строки и используйте команду с точкой, чтобы преобразовать файл gv в графический файл png.
graph
использование графика — Опишите отношения
digraph
использовать -> Опишите отношения
Сложный пример
Взаимодействовать с python
Мощный и удобный метод Graphviz для рисования диаграмм / блок-схем позволяет нам легко думать о машинном обучении. Decision Tree Метод отображения. К счастью, scikit-learn предоставляет .dot Файловый интерфейс, конкретные операции следующие:
вpythonВ среде редактирования:
Войдите в интерфейс командной строки Windows, переключитесь на cd tree.dot Путь, выполнить
Интеллектуальная рекомендация
Меч относится к предложению + 43: количество N сиша + Java
Оригинальное название: бросить кубики на землю, все точки кости сталкиваются с точкой точки кости. Введите n, напечатали вероятность всех возможных значений. (6 сторон каждой кости, точки от 1 до 6) Р.
Введение в Python 4
функция ввода Использование функции Функция input () является функцией ввода. Функция input () — это функция ввода. Когда вы пишете вопрос в скобках функции, функция input () будет отображать вопрос в.
Основные операции в R 01
Повторите основную операцию секретной книги ниндзя языка R учителя Се Иихуэй.
Мастерство, создание американской легенды очистки воды
Мастера — это не только технические специалисты и квалифицированные мастера, которые могут решить некоторые практические проблемы в производстве и жизни, но также авангарды, которые могут руководить п.
курсы памяти Лу Feifei (а, понимать память понимания мозга)
Понимание памяти, что память? Понимание памяти, что память? 1 Понимание мозга 2 Что такое память Функция 3 Память 3.1 общие воспоминания путь 3.2 Факторы, влияющие на память 4 запоминающий материал Че.
User Guide¶
graphviz provides a simple pure-Python interface for the Graphviz graph-drawing software. It runs under Python 3.7+. To install it with pip, run the following:
For a system-wide install, this typically requires administrator access. For an isolated install, you can run the same inside a venv or a virtualenv.
After installing Graphviz, make sure that its bin/ subdirectory containing the dot layout command for rendering graph descriptions is on your systems’ PATH (sometimes done by the installer; setting PATH on Linux, Mac, and Windows): On the command-line, dot -V should print the version of your Graphiz installation.
Windows users might want to check the status of known issues (gvedit.exe, sfdp, commands) and consider trying an older archived version as a workaround (e.g. graphviz-2.38.msi).
See the downstream conda-forge distribution conda-forge/python-graphviz (feedstock), which should automatically conda install conda-forge/graphviz (feedstock) as dependency.
Basic usage¶
The graphviz package provides two main classes: graphviz.Graph and graphviz.Digraph . They create graph descriptions in the DOT language for undirected and directed graphs respectively. They have the same API .
Graph and Digraph produce different DOT syntax and have different values for directed .
Create a graph by instantiating a new Graph or Digraph object:
Their constructors allow to set the graph’s name identifier, the filename for the DOT source and the rendered graph, an optional comment for the first source code line, etc.
Add nodes and edges to the graph object using its node() and edge() or edges() methods:
The node() method takes a name identifier as first argument and an optional label . The edge() method takes the names of start node and end node, while edges() takes an iterable of name pairs. Keyword arguments are turned into (node and edge) attributes (see extensive Graphviz docs on available attributes).
Check the generated DOT source code:
Use the render() method to save the DOT source code and render it with the default dot layout engine (see below for using other layout engines).
Passing view=True will automatically open the resulting (PDF, SVG, PNG, etc.) file with your system’s default viewer application for the rendered file type.
Backslash-escapes and strings of the form <. > have a special meaning in the DOT language and are currently passed on as is by this library. If you need to render arbitrary strings literally (e.g. from user input), consider wrapping them with the graphviz.escape() function first. See the sections on Backslash escapes and Quoting and HTML-like labels below for details.
Formats¶
To use a different output file format than the default PDF, you canuse the format argument when creating your Graph or Digraph object:
You can also change the format attribute on an existing graph object:
Piped output¶
To directly access the raw results from the Graphviz dot layout command as binary bytes or as decoded str (for plain-text formats like SVG) instead of writing to a file, use the pipe() method of your Graph or Digraph object:
Because pipe() returns the raw stdout from the layout subprocess by default ( bytes ), you usually want to decode the return value when piping into formats like ‘svg’ or ‘plain’ ,
The output for pipe() is buffered in memory, so avoid this method if the data size is large.
Jupyter notebooks¶
Graph and Digraph objects have a _repr_mimebundle_() method so they can be rendered and displayed directly inside a Jupyter notebook. For an example, check the examples/graphviz-notebook.ipynb file in the source repository/distribution (or the same notebook in nbviewer).
This also allows direct displaying within the Jupyter Qt Console (also the one inside Spyder IDE):
By default _repr_mimebundle_() uses ‘svg’ format. You can use the graphviz.set_jupyter_format() to override the default format that is used for displaying in IPython/Jupyter. (example, nbviewer).
You can also use display_svg() , display_png() , or .display_jpeg() from IPython.display to display the rendered Graph or Digraph as SVG, PNG or JPEG in IPython/Jupyter.
Styling¶
Use the graph_attr , node_attr , and edge_attr arguments of the Graph and Digraph constuctors to change the default attributes for your graph, nodes, and edges.
After creation, the graph_attr , node_attr , and edge_attr attributes be edited on instances:
Attributes¶
To directly add DOT att_stmt attribute statements, call the attr() method of the Graph or Digraph instance with the wanted target as first argument and the attributes as keyword args.
Attribute statements affect all later graphs, nodes, or edges within the same (sub-)graph.
If you omit the first attr() argument, the method can be used to set arbitrary attributes as key-value pairs targeting the current (sub-)graph (e.g. for rankdir , label , or setting rank=’same’ within a subgraph context, example ):
Node ports & compass¶
The edge() and edges() methods use the colon-separated node[:port[:compass]] format for tail and head nodes. This allows to specify an optional node port plus an optional compass point the edge should aim at for the given tail or head node ( example ).
As colons are used to indicate port and compass for edges, node names containing one or more literal colons : are currently not supported. GH #54
There is no such restriction for the label argument, so you can work around by choosing a colon-free name together with the wanted label as demonstrated below
Backslash escapes¶
The Graphviz layout engines support a number of escape sequences such as \n , \l , \r (for placement of multi-line labels: centered, left-justified, right-justified) and \N , \G , \L (expanded to the current node name, graph name, object label). To be able to use them from this library (e.g. for labels), backslashes in strings are (mostly) passed on as is.
This means that literal backslashes need to be escaped (doubled) by the user. As the backslash is also special in Python string literals a second level of doubling is needed. E.g. label=’\\\\’ for a label that is rendered as single literal backlash: \ .
Doubling of backslashes can be avoided by using raw string literals ( r’. ‘ ) instead. This is similar to the solution proposed for the stdlib re module. See also https://en.wikipedia.org/wiki/Leaning_toothpick_syndrome.
To disable any special character meaning in a string (e.g. from user input to be rendered literally), use the graphviz.escape() function (similar to the re.escape() function):
To prevent breaking the internal quoting mechanism, the special meaning of \" as a backslash-escaped quote has been disabled since version 0.14 of this library. E.g. both label=’"’ and label=’\\"’ now produce the same DOT source [label="\""] (a label that renders as a literal quote). See also examples/graphviz-escapes.ipynb (nbviewer).
Quoting and HTML-like labels¶
The graph-building methods of Graph and Digraph objects automatically take care of quoting (and escaping quotes) where needed (whitespace, keywords, double quotes, etc.):
If a string starts with ‘<‘ and ends with ‘>’ , it is passed on as is, i.e. without quoting/escaping: The content between the angle brackets is treated by the Graphviz layout engine as special HTML string that can be used for HTML-like labels:
For strings that should literally begin with ‘<‘ and end with ‘>’ , use the graphviz.nohtml() function to disable the special meaning of angled parenthesis and apply normal quoting/escaping:
Before version 0.8.2 , the only workaround was to add leading or trailing space ( label=’ <>’ ):
Subgraphs & clusters¶
Graph and Digraph objects have a subgraph() method for adding a subgraph to the instance.
There are two ways to use it: Either with a ready-made instance of the same kind as the only argument (whose content is added as a subgraph) or omitting the graph argument (returning a context manager for defining the subgraph content more elegantly within a with -block).
First option, with graph as the only argument:
Second usage, with a with -block (omitting the graph argument):
Both produce the same result:
If the name of a subgraph begins with ‘cluster’ (all lowercase), the layout engine treats it as a special cluster subgraph ( example ). See the Subgraphs and Clusters section in DOT language.
When subgraph() is used as a context manager, the new graph instance is created with strict=None copying the parent graph values for directory , engine , format , renderer , formatter , and encoding :
These copied attributes are only relevant for rendering the subgraph independently (i.e. as a stand-alone graph) from within the with -block.
Engines¶
To use a different layout engine than the default dot when rendering your graph, you can use the engine argument on the constructor of Graph or Digraph .
You can also change the engine attribute on an existing instance:
neato no-op flag¶
The neato layout engine supports an additional rendering flag that allows more control over the node positioning and the edge layout via the pos, overlap, and splines attributes.
Use the neato_no_op keyword argument of render() or pipe() to pass it to the layout command:
Unflatten¶
To prepocess the DOT source of a Graph or Digraph with the unflatten preprocessor (manpage, PDF), use the unflatten() method.
unflatten() improves the aspect ratio of graphs with many leaves or disconnected nodes.
The method returns a Source object that you can render() , view() , etc. with the same basic API as Graph or Digraph objects (minus modification, see details below ).
Custom DOT statements¶
To add arbitrary statements to the created DOT source, you can use the body attribute of Graph and Digraph objects. It holds the verbatim list of ( str ) lines to be written to the source file (including their final newline). Use its append() or extend() method:
Note that you might need to correctly quote/escape identifiers and strings containing whitespace or other special characters when using this method.
Using raw DOT¶
To render a ready-made DOT source code string (instead of assembling one with the higher-level interface of Graph or Digraph ), create a graphviz.Source object holding your DOT string:
Use the render() method to save and render it:
Apart from lacking editing methods, Source objects have the same basic API as the higher-level Graph and Digraph objects (e.g. save() , render() , view() , pipe() methods, engine and format attributes, Jupyter notebook _repr_mimebundle_() , etc. See API docs ).
Existing files¶
To directly render an existing DOT source file (e.g. created with other tools), you can use the graphviz.render() function.
To directly display the rendered visualization of an existing DOT source file inside a Jupyter notebook or Qt Console, you can use graphviz.Source.from_file() (alternative constructor):
Note that render() and view() on Source instances returned by graphviz.Source.from_file() skip writing the loaded file back. The same holds for save() . The instances resolve default .save(skip_existing=None) to .save(skip_existing_run=True) to skip writing the read source back into the same file (specifically the same path that it was loaded from). Call .save(skip_existing=False) if you want to re-write the loaded source.
Before version 0.18 of this library, Source.save() , Source.render() , and Source.view() , wrote the content read into source back into the file. It was advised to use graphviz.render() and graphviz.view() to directly work on files if the superflous saving needed to be avoided.
Integration with viewers¶
On platforms such as Windows, viewer programs opened by render() with view=True (or eqivalently with the view() shortcut-method) might lock the (PDF, PNG, etc.) file for as long as the viewer is open (blocking re-rendering it with a Permission denied error).
Использование Graphviz для построения блок-схем
Мы создаем ПО для разработки и поддержки баз данных Oracle, и статический анализатор PL/SQL является одной из основных фич наших приложений. Кто знаком с Oracle, тот хорошо знает что такое PL/SQL.
Известная поговорка гласит: «Лучше один раз увидеть, чем сто раз услышать». Поэтому мы решили заимпрувить статический анализатор таким образом, чтобы он визуализировал код в виде блок-схем (Flowcharts) и диаграмм вызовов (Call Trees). Хоть и нарисовать блоки и их связи несложно, оптимизировать их расположение на «листе» представлялось задачей, требующей значительных усилий. Чтобы стрелки минимально пересекались и обтекали блоки, блоки объединялись в группы, и диаграмма при этом не превращалась в «кашу», нужно было потратить много сил и времени.
И тогда мы решили поискать готовое решение, дабы не изобретать велосипед. Наше внимание сразу привлек Graphviz – open source решение по визуализации диаграмм. Первые его версии были разработаны компанией AT&T, а теперь он доступен как набор утилит и библиотек, а также в исходниках под лицензией Eclipse Public License (EPL).
Его движок диаграмм использует язык описания графов DOT, который представляет собой текстовое описание структуры графа: вершины, их связи, группы и атрибуты для их визуального оформления.
Описание простейшего графа:
Если необходимо добавить узлам атрибуты, например подписи, то необходимо отдельно описать узлы:
Далее покажу на примере простой процедуры на PL/SQL:
Код понятен, даже если вы не знакомы с синтаксисом PL/SQL.
А теперь опишем этот код на языке DOT. Пояснения снова излишни:
Теперь можно «скормить» этот файл Graphviz, подставив соответственно вместо %PNGFILE% и %DOTFILE% имена выходного (png) и входного (dot) файлов:
При помощи Graphviz из описания выше получается такая картина:
Наглядно, но весьма аскетично.
Можно сделать диаграмму привлекательнее, добавив атрибуты для определения формы блоков (shape=diamond) , подписи стрелок (label=»Yes») и цвета color , fontcolor .
Также мы можем объединить в подграф блоки, которые являются исполняемыми. Это реализуется конструкцией subgraph <> , внутри которой мы можем перечислить имена блоков, включенных в подграф, и указать атрибуты для визуального оформления (цвет рамки).
Получается вполне симпатичная блок-схема, которую и людям показать не стыдно.
Чтобы код могли читать не только программисты, но и «простые смертные», мы придумали такую фишку: приделали распознавание специальных тегов в комментариях, которые бы разработчик писал как псевдокод – язык описания алгоритмов. Это помогло увеличить ценность блок-схемы, которая теперь может отображать бизнес-логику, а не только визуализировать листинг.
Вуаля! Graphviz дает возможность делать потрясающие визуализации с минимальными затратами.
What’s Graphviz?
Graphviz is open source graph visualization software. Graph visualization is a way of representing structural information as diagrams of abstract graphs and networks. It has important applications in networking, bioinformatics, software engineering, database and web design, machine learning, and in visual interfaces for other technical domains.
Install Graphviz
Under Linux environment, execute the following command to install Graphviz and show detail information of it:
Layout Commands
The following layout commands are available when Graphviz is installed:
Commands Description dot hierarchical or layered drawings of directed graphs. This is the default tool to use if edges have directionality. neato spring model layouts. This is the default tool to use if the graph is not too large (about 100 nodes) and you don’t know anything else about it. Neato attempts to minimize a global energy function, which is equivalent to statistical multi-dimensional scaling. fdp spring model layouts similar to those of neato, but does this by reducing forces rather than working with energy. sfdp multiscale version of fdp for the layout of large graphs. twopi radial layouts, after Graham Wills 97. Nodes are placed on concentric circles depending their distance from a given root node. circo circular layout, after Six and Tollis 99, Kauffman and Wiese 02. This is suitable for certain diagrams of multiple cyclic structures, such as certain telecommunications networks. Editor
The editor vimdot is included in Graphviz:
The Graphviz dot mode for emacs is also a useful tool for edit Graphvize.
Command-line Syntax
All Graphviz programs have a similar invocation:
If no input files are supplied, the program reads from stdin.
Flags
-Gname[=value]
Set a graph attribute, with default value = true .
-Nname[=value]
Set a default node attribute, with default value = true .
-Ename[=value]
Set a default edge attribute, with default value = true .
-Klayout
Specifies which default layout algorithm to use, overriding the default from the command name. For example, running dot -Kneato is equivalent to running neato.
-Tformat[:renderer[:formatter]]
Set output language to one of the supported formats. By default, attributed dot is produced.
Depending on how Graphviz was built, there may be multiple renderers for generating a particular output format, and multiple formatters for creating the final output. For example, a typical installation can produce PNG output using either the Cairo or GD library. The desired rendering engine can be specified after a colon. If there are multiple formatting engines available, the desired one can be specified in a similar fashion after the rendering engine. Thus, -Tpng:cairo specifies PNG output produced by Cairo (using the Cairo’s default formatter), and -Tpng:cairo:gd specifies PNG output produced by Cairo formatted using the GD library.
If no renderer is specified, or a renderer but no formatter, the default one is invoked. The flag -Tformat: produces a list of all of the renderers available for the specified format, the first one listed with a prefix matching format being the default. Using the -v flag will print which format, renderer, and formatter are actually used.
-llibrary
User-supplied, device-dependent library text. Multiple flags may be given. These strings are passed to the code generator at the beginning of output.
For PostScript output, they are treated as file names whose content will be included in the preamble after the standard preamble. If library is the empty string «» , the standard preamble is not emitted.
Sets no-op flag in neato. If set, neato assumes nodes have already been positioned and all nodes have a pos attribute giving the positions. It then performs an optional adjustment to remove node-node overlap, depending on the value of the overlap attribute, computes the edge layouts, depending on the value of the splines attribute, and emits the graph in the appropriate format. If num is supplied, the following actions occur:
Equivalent to -n.
Use node positions as specified, with no adjustment to remove node-node overlaps, and use any edge layouts already specified by the pos attribute. neato computes an edge layout for any edge that does not have a pos attribute. As usual, edge layout is guided by the splines attribute.
-ooutfile
Write output to file outfile. By default, output goes to stdout.
-O
Automatically generate output file names based on the input file name and the various output formats specified by the -T flags.
-P
Automatically generate a graph that shows the plugin configuration of the current executable. e.g. dot -P -Tps | lpr
-q
Suppress warning messages.
-s[scale]
Set input scale to scale. If this value is omitted, 72.0 is used. This number is used to convert the point coordinate units used in the pos attribute into inches, which is what is expected by neato and fdp. Thus, feeding the output of a graph laid out by one program into neato or fdp almost always requires this flag. Ignored if the -n flag is used.
-V
Emit version information and exit.
-v
-x
In neato, on input, prune isolated nodes and peninsulas. This removes uninteresting graph structure and produces a less cluttered drawing.
-y
By default, the coordinate system used in generic output formats, such as attributed dot, extended dot, plain and plain-ext, is the standard cartesian system with the origin in the lower left corner, and with increasing y coordinates as points move from bottom to top. If the -y flag is used, the coordinate system is inverted, so that increasing values of y correspond to movement from top to bottom.
Print usage information, then exit.
If multiple -T flags are given, drawings of the graph are emitted in each of the specified formats. Multiple -o flags can be used to specify the output file for each format. If there are more formats than files, the remaining formats are written to stdout.
Note that the -G , -N and -E flags override any initial attribute declarations in the input graph, i.e., those attribute statements appearing before any node, edge or subgraph definitions. In addition, these flags cause the related attributes to be permanently attached to the graph. Thus, if attributed dot is used for output, the graph will have these attributes.
Environment Variables
GDFONTPATH
List of pathnames giving directories which a program should search for fonts. Overridden by DOTFONTPATH. Used only if Graphviz is not built with the fontconfig library.
DOTFONTPATH
List of pathnames giving directories which a program should search for fonts. Overridden by fontpath. Used only if Graphviz is not built with the fontconfig library.
SERVER_NAME
If defined, this indicates that the software is running as a web application, which restricts access to image files. See GV_FILE_PATH.
GV_FILE_PATH
If SERVER_NAME is defined, image files are restricted to exist in one of the directories specified by GV_FILE_PATH. This last is a list of directory pathnames, separated by semicolons in Windows or by colons otherwise. Note that sometimes, when using one of the layout programs in a web script, it is not enough to use an export command but rather the variables should be set when the command is run, for example:
Note that the image files must really reside in one of the specified directories. If the image file is specified as an absolute or relative pathname, a warning is given and only the base name is used.
GVBINDIR
Indicates which directory contains the Graphviz config file and plug-in libraries. If it is defined, the value overrides any other mechanism for finding this directory. If Graphviz is properly installed, it should not be needed, though it can be useful for relocation on platforms not running Linux or Windows.
DOT Language
The DOT Language is a plain text graph description language. It is a simple way of describing graphs that both humans and computer programs can use. DOT graphs are typically files that end with the .gv (or .dot) extension. The .gv extension is preferred in cases where there could be confusion with the .dot file extension used by early (pre-2007) versions of Microsoft Word.
The keywords node, edge, graph, digraph, subgraph, and strict are case-independent. Note also that the allowed compass point values are not keywords, so these strings can be used elsewhere as ordinary identifiers and, conversely, the parser will actually accept any identifier.
An ID is one of the following:
- Any string of alphabetic ( [a-zA-Z\200-\377] ) characters, underscores ( _ ) or digits ( [0-9] ), not beginning with a digit;
- a numeral [-]?(.[0-9]+ | [0-9]+(.[0-9]*)?) ;
- any double-quoted string ( «. » ) possibly containing escaped quotes ( ‘ );
- an HTML string ( <. > ).
An ID is just a string; the lack of quote characters in the first two forms is just for simplicity. There is no semantic difference between abc_2 and «abc_2» , or between 2.34 and «2.34» . Obviously, to use a keyword as an ID, it must be quoted. Note that, in HTML strings, angle brackets must occur in matched pairs, and newlines and other formatting whitespace characters are allowed. In addition, the content must be legal XML, so that the special XML escape sequences for » , & , < , and > may be necessary in order to embed these characters in attribute values or raw text. As an ID, an HTML string can be any legal XML string. However, if used as a label attribute, it is interpreted specially and must follow the syntax for HTML-like labels.
Both quoted strings and HTML strings are scanned as a unit, so any embedded comments will be treated as part of the strings.
An edgeop is -> in directed graphs and — in undirected graphs.
The language supports C++-style comments: /* */ and // . In addition, a line beginning with a ‘#’ character is considered a line output from a C preprocessor (e.g., # 34 to indicate line 34 ) and discarded.
Semicolons and commas aid readability but are not required. Also, any amount of whitespace may be inserted between terminals.
As another aid for readability, dot allows double-quoted strings to span multiple physical lines using the standard C convention of a backslash immediately preceding a newline character2. In addition, double-quoted strings can be concatenated using a ‘+’ operator. As HTML strings can contain newline characters, which are used solely for formatting, the language does not allow escaped newlines or concatenation operators to be used within them.
Digraph or Graph
A graph must be specified as either a digraph (有向图) or a graph (无向图). Semantically, this indicates whether or not there is a natural direction from one of the edge’s nodes to the other. Lexically, a digraph must specify an edge using the edge operator -> while a undirected graph must use — . Operationally, the distinction is used to define different default rendering attributes. For example, edges in a digraph will be drawn, by default, with an arrowhead pointing to the head node. For ordinary graphs, edges are drawn without any arrowheads by default.