There are other types of formats that you can save data in beyond the tabular format, beyond, or the CSV file or text file. These are also textual formats, but they are a little bit different for, from the tabular data that we've talked about before. And the two main functions for writing out data and f, are dumping and dputing. So, and, and the idea behind these types of formats is they're text formats, but they're not really, they're not really formatted in a way that's, in the same as like a table because they contain a little bit more meta-data. So data about, for example, the type of the data in, in each class, object for example. So if you, if you dump or dput a data frame. It will include in the output, that the class of each column, of the data frame, so that you don't have to specify it when you read it in. And so the advantage of, of doing, using this type of mechanism to store data or to read, or to read data, is that you don't have, it's still a textual format, which can be useful, but it also contains metadata, so that you don't have to specify it every single time you read it in. Because that, if you don't, ca, if the metadata do not get carried with the data set itself, then it, they ca, they can get lost if you, if they get transferred somewhere else and if you don't remember what the metadata are, for example the classes of the different columns, then you kind of have to reconstruct that from scratch. So that's one advantage of using, using a function like dump or dput to, to output data from R. And similarly the, the, the, the functions for reading data using, fr, that haven't been outputted from dump or dput are source and, dget. So in general, the textual formats are very nice formats for storing data because, there's a number of different types of, different advantages to them. First of all, they're editable, so you can, if you want to you can edit them. I wouldn't say this is something that I would advice, but because of you wanted something that's reproducible. But, for example if something gets corrupted then you can look at the file to see if it's possible to recover it. So textual formats can be a little longer lived, if you're going to be storing data for a long time, sometimes it's useful to, if it's possible to use a type of textual format so that you can avoid problem, potential problems with corruption. Textual formats can also work better if you're using like a version control program, like subversion or git, where you're tracking changes between documents. and, and those types of programs tend to be much more useful with textual data rather than binary data, so that you can track changes meaningfully. Textual formats adhere to the general kind of Unix philosophy, which is to store all kinds of data, which generally stores all kinds of data in text. But the one downside of textual formats is that they tend not to be space efficient, so they tend to, they tend to take up a lot of space, and so, it often need to be compressed. So, d, the dput function takes an arbitrary R object, and it will, use, it will take most types of R objects except for some more exotic ones, and it will create some R code that will essentially reconstruct the object in R. So here's I'm creating a small data frame, it's got two columns, the first column is called A the second column is called B, and then I'm going to dput this data frame. And you'll see the out, if you discall dput it'll just output the results to the console. And you can see that what I've done is that. What it does, it, it's re, it's constructed some R code. For example, it's creating this list that has these two elements in it. And you can see that each element has has the data that's in it. And it has the names embedded here, it's got the row names here. And it has the class of the object which, in this case, is the data frame. And so, all the metadata here like the row names and the names and the class are all included in the output. Now, of course, you generally don't want to print this to the console, that's not particularly useful, you probably want to save it to a file. So you can dput the file to a file and then later on, you can read it into R using dget, and when you dget the object, you will get this object and you will see that it's, you have kind of reconstructed the object from before. So the dput function, essentially writes R code, which can be used to reconstruct an R object. The dump function is a lot like dget however, the difference is that dget can only be used on a single R object. Whereas dump can be used on multiple R objects and so what you do is what you pass a dump is the character vector which contains the names of the objects. So here I created two objects one called x, the other called y and when I pass the dump. Is are the names of those objects? The names are X and Y. And I give it a file, that I want to store the da, the objects in. And then I can remove them if I want to, but to read those objects back into R, I can call the source function on that file and you'll see that the Y object and the X object have been reconstructed.
