Welcome to this lesson on writing table data to text files. In today's digital world, storing and sharing data efficiently is essential. Text files are a common way to achieve this due to their simplicity and compatibility with various systems. In this lesson, our goal is to learn how to write formatted table data into a text file using tabs as delimiters.

By the end of this lesson, you will be able to take a structured data format and write it to a text file using R. Let’s dive into this skill and build on what you've learned about parsing tables from text and CSV files.

Before we proceed, let's briefly recall two key concepts: data frames in R and basic file handling.

• Data Frames: In R, data frames allow you to store a collection of items, such as rows in a table. This step is crucial as it helps organize your data into a structured format.

• File Handling: We previously covered basic reading operations. Now, we move to writing data. The write.table() function is used for writing. Remember to specify the delimiter and other relevant parameters correctly.

These foundational concepts will guide us in the process of writing table data into a text file.

Let's begin by structuring our table data using a data frame. This format helps us represent rows and columns in a simple and organized manner. Here's an example of how we might represent some tabular data:

R
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1data <- data.frame(
2  Name = c("John", "Alice", "Bob"),
3  Age = c(28, 34, 23),
4  Occupation = c("Engineer", "Doctor", "Artist")
5)

Each column represents a category like Name, Age, and Occupation. Structuring data like this makes adding or modifying rows simple and ensures easy writing to files.

In R, writing data with specific delimiters such as tabs can be easily handled using the write.table() function. This function accepts a sep argument to specify the delimiter. Consider the example:

R
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1output_file_path <- "output.txt"
2write.table(data, file = output_file_path, sep = "\t", row.names = FALSE, quote = FALSE)

• sep = "\t": This argument specifies that a tab character should separate elements when writing to the file.
• write.table(): Writes the data frame to the specified file, with tabs as delimiters, where:
  • row.names = FALSE: Ensures that row indices are not written to the file.
  • quote = FALSE: Ensures that character strings are not enclosed in quotes.

It is beneficial to confirm that the operations were successful by viewing the content of your output file. Here is the output.txt file after writing the data to it:

Plain text
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1Name    Age Occupation
2John    28  Engineer
3Alice   34  Doctor
4Bob     23  Artist

As you see, the data is structured with tabs as delimiters, and we can verify that the data has been correctly written and formatted by inspecting the output.

In this lesson, you learned how to effectively structure, write, and verify data stored in a text file using R. We started with preparing data using data frames, then utilized R's file-handling functions to write this data using tabs as delimiters.

Now, we encourage you to engage with the practice exercises that follow this lesson. Apply what you've learned to reinforce your understanding and gain confidence. Keep experimenting with different data structures, adapt them, and ensure your outputs meet your expectations. Well done on progressing through this important lesson.