It only tells R how to identify missing values in the raw data that we are importing. In the R data frame that is created, missing data will still be represented with the special NA value.
Sometimes you will encounter plain text files that contain values separated by tab characters instead of a single space. Files like these may be called tab separated value or tsv files, or they may be called tab-delimited files. To import tab separated value files in R, we use a variation of the same program we just saw.
We just need to tell R that now the values in the data will be delimited by tabs instead of a single space. Those values were imported as a data frame, and we assigned that data frame to the R object called tab.
But, apparently, they are common enough to warrant a shortcut function in the readr package. Yet another type of plain text file we will discuss is called a fixed width format or fwf file. Take a look at this example:. As you can see, a hallmark of fixed width format files is inconsistent spacing between values. For example, there is only one single space between the values and Female in the fourth row.
But, there are multiple spaces between the values 65 and So, how do we tell R which characters including spaces go with which variable? Well, if you look closely you will notice that all variable values start in the same column. If you are wondering what I mean, try to imagine a number line along the top of the data:. This number line creates a sequence of columns across your data, with each column being 1 character wide. Notice that spaces are also considered a character with width just like any other.
We can use these columns to tell R exactly which columns contain the values for each variable. Those values were imported as a data frame, and we assigned that data frame to the R object called fixed. For example:. Instead, it parses the entire data set as a single character column. However, because all the variables start in the same column, we can tell R how to parse the data correctly. We can actually do this in a couple different ways:. One way to import this data is to tell R how many columns wide each variable is in the raw data.
We do that like so:. The value passed to the file argument should be file path that tells R where to find the data set on your computer. The value passed to this argument tells R the width i. This is an example of nesting functions.
Another way to import this data is to tell R how which columns each variable starts and stops at in the raw data. As a shortcut, either of the methods above can be written using named vectors. The final type of plain text file that we will discuss is by far the most common type used in my experience. Unlike space and tab separated values files, csv file names end with the. Although, csv files are plain text files that can be opened in plain text editors such as Notepad for Windows or TextEdit for Mac, many people view csv files in spreadsheet applications like Microsoft Excel, Numbers for Mac, or Google Sheets.
Those values were imported as a data frame, and we assigned that data frame to the R object called csv. For the most part, the data we imported in all of the examples above was relatively well behaved. Take a look at this csv file for a few seconds. See if you can spot them all. When people record data in Microsoft Excel, they do all kinds of crazy things.
Row two is a blank line. Maybe the study staff finds it aesthetically pleasing? Row three contains some variable descriptions. Row 7, column D is a missing value. Remove replacement character. Remove non-alphanumeric characters. Other Strip all e-mails. Remove BBCode tags Forum. Strip all HTML tags. Remove all ids. Remove all classes. Remove inline styles.
Decode URL-encoded characters. Links Remove all web urls. Convert urls to links. Letter case Uppercase. Sentence case. Capitalize each word. Do not change. Quotes Smart quotes to regular. Regular quotes to smart. Remove repeating words. Trim Remove characters from left. Remove characters from right. Writing Fix spaces after each punctuation mark.
Convert common shorthand to full words. You can also not change the font size or font color of any of the text in a plain text file. What can and cannot be done in a text file? Tip In short a text file only supports text and nothing else. Tip Open the a text file in a rich text editor such as Microsoft WordPad or a word processor. Note You could indent text in a text file using the Tab or the spacebar. Related information See our document , plain text file , and rich text file pages for further information and related links on each of these terms.
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