{"id":393,"date":"2020-08-26T14:42:49","date_gmt":"2020-08-26T14:42:49","guid":{"rendered":"https:\/\/aaidm.buas.nl\/?page_id=393"},"modified":"2020-08-26T15:22:33","modified_gmt":"2020-08-26T15:22:33","slug":"pr1-preparation-for-week-7-reading-a-file","status":"publish","type":"page","link":"https:\/\/aaidm.buas.nl\/?page_id=393","title":{"rendered":"PR1 – Preparation for Week 7 – Reading a file"},"content":{"rendered":"\n
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uthor:<\/td>Carlos Santos<\/td><\/tr>
Learning Line:<\/td>Programming<\/td><\/tr>
Course:<\/td>PR1: Introduction to Programming<\/td><\/tr>
Week:<\/td>6<\/td><\/tr>
Competencies:<\/td>Students will be able to effectively define and use variables, programming flow control.<\/td><\/tr>
BoKS:<\/td>\u00ad 3bK2, The student understands the principles of data related software like Python, R, Scala and\/or Java and knows how to write (basic) scripts.<\/td><\/tr>
Learning Goals:<\/td>Able read text files<\/td><\/tr><\/tbody><\/table><\/figure>\n<\/div><\/div>\n\n\n\n

Text File I\/O<\/h2>\n\n\n\n

Before we start with how to handle files within Python, it\u2019s important to understand what is a file.<\/p>\n\n\n\n

At its core, a file is a contiguous set of bits (0 an 1s). This data is organized in a specific format and can be anything as simple as a text file or as complicated as a encoded image or an program executable.<\/p>\n\n\n\n

The data stored within files represents and may have different functions within the computer, it depends on the format specification used, which is typically represented by an extension. <\/p>\n\n\n\n

For example, a file that has an extension of\u00a0.gif<\/code>\u00a0most likely conforms to the\u00a0Graphics Interchange Format<\/a>\u00a0specification. There are hundreds, if not thousands, of\u00a0file extensions<\/a>\u00a0out there. For this tutorial, you\u2019ll only deal with\u00a0text files like .txt<\/code>\u00a0or\u00a0.csv<\/code>\u00a0file extensions.<\/p>\n\n\n\n

Text files are structured as a sequence of\u00a0characters, ended by a special character EOF (End of File). On most operating systems the file format that allows only plain text content with no formatting. Such files can be viewed and edited on\u00a0terminals and text editors, usually with additional information indicating an encoding.<\/p>\n\n\n\n

Text files have the typical characters like letters and digits, and punctuation, but also multiple special characters, like spaces, tabs and new lines. Interesting to know is that, different operating systems may use different rules, for example in Windows, each line of text separated by a two-character combination:\u00a0carriage return<\/a>\u00a0(CR) and\u00a0line feed<\/a>\u00a0(LF), while in Unix-lile OS, lines are separated by LFs and in MacOS are CR.<\/p>\n\n\n\n

File Encoding<\/h3>\n\n\n\n

In\u00a0computing,\u00a0data storage, and\u00a0data transmission,\u00a0encoding<\/strong>\u00a0is used to represent a repertoire of\u00a0characters for textual data.<\/p>\n\n\n\n

Early character codes associate optical representation or a binary value. And they could only represent a small subset of the characters used in\u00a0written languages, sometimes restricted to\u00a0Latin based characters, and digits representation and some\u00a0punctuation\u00a0only. With the reduction of the cost and evolution of transmissions more elaborate character codes (such as\u00a0Unicode<\/a>) may represent most of the characters used in many written languages. Character encoding using internationally accepted standards permits worldwide interchange of text in electronic form.<\/p>\n\n\n\n

Character<\/th>Unicode code point<\/th>Glyph<\/th><\/tr>
Latin A<\/td>U+0041<\/td>\u0391<\/td><\/tr>
Latin sharp S<\/td>U+00DF<\/td>\u00df<\/td><\/tr>
Han for East<\/td>U+6771<\/td>\u6771<\/td><\/tr>
Ampersand<\/td>U+0026<\/td>&<\/td><\/tr>
Inverted exclamation mark<\/td>U+00A1<\/td>\u00a1<\/td><\/tr>
Section sign<\/td>U+00A7<\/td>\u00a7<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Text Editors<\/h2>\n\n\n\n

There are multiple text editors, and most of the programming editing interfaces are in their essence text editors, which attached compilers or interpreters. <\/p>\n\n\n\n

If you do use one, or do not have one you prefer, I suggest you get familiarized with one, you will be using it a lot, and there are specific features, like encoding, file browsing, syntax highlighting, macros, integration with source control, that can be very useful. Here are some of the most known:<\/p>\n\n\n\n