I imported a csv file into R. The first column has my observations and I have 5 variables. However, when I import it into R it takes my column of observations as a variable, and tells me I have 6 variables. How do I make it understand that the first column of "cars" is a column of observations? I attach a picture for reference.
Thank you,
Marianaenter image description here
You should be able to specify this with the row.names parameter in read.csv. Although I can't say exactly what to type since I don't have the original dataset, it should be something like:
read.csv(file = "myfile.csv", row.names = 1, [other options])
indicating that row names can be found in the first column.
If you're using some other method of importing the file (e.g. by using the RStudio graphical interface), there should be an option somewhere along the way to specify the location of row names.
Alternatively, a possibly easier approach is suggested by the read.csv documentation:
If row.names is not specified and the header line has one less entry than the number of columns, the first column is taken to be the row names. This allows data frames to be read in from the format in which they are printed. If row.names is specified and does not refer to the first column, that column is discarded from such files.
Try deleting the X in the top left corner of your .csv file (and delete the comma that follows it) and see if that gets you anywhere.
EDIT Marius has the right suggestion, by the way - just ignore the junk column and work with row numbers instead. (What's the harm?)
Related
I am trying to read a special type of file (the format is called AGS) which looks like in the image:
This is basically a TEXT file, which contains many tables with different dimensions inside, separated by 2 (but sometimes more) empty rows. As you might guess, the problem is related to the fact that these tables have different number of columns and obviously different column names.
The first row in each table (here tables are denoted as GROUP) shows the name of the table, e.g. LOCA, HDPH, etc. The second row shows the column names. The third row shows the units of each column. All the other rows show the observations. In each row, columns are separated by commas and values are inside double quotes.
I am struggling to read this type of file. The ideal output would be to have each of these tables into separated data frames. Any help and ideas are much appreciated.
An example file can be downloaded here: example AGS file
I'm a new who is exploring bioinformatics via R. Right now I've encounter a trouble, where I imported my data in excel into R through changing it into csv format and using read.csv command, as you see in the pic there are 37 variables (column) where first column is supposed to be considered as fixed factor. And I would like to match it with another matirx which has only 36 variables in the downstream processing, what should I do to reduce variable numbers by fixing first column?
Many thanks in advance.
sure, I added str() properties of my data here.
If I am not mistaken, what you are looking for is setting the "Gene" column as metadata, indicating what gene those values in every row correspond to. You can try then to delete the word "Gene" in the Excel file because when you import it with the read.csv() function, the argument row.names = TRUE is set as default when "there is a header and the first row contains one fewer field than the number of columns".
You can find more information about this function using ?read.csv
I couldn't find the answer in any previously asked questions, but I believe this is an easy one.
I have the below two lines of code, which take in data from excel in a specific range (using readxl for this). The range itself only goes through row 2589 in the excel document, but it will update dynamically (it's a time series) and to ensure I capture the different observations (rows) as they're added, I've included rows to 10000 in the read_excel range argument.
In the end, I'd like to run charts on this data, but a key part of this is identifying the last used row, without manually updating the code row for the latest date. I've tried using nrow but to no avail.
Raw_Index_History <- read_excel("RData.xlsx", range = "ReturnsA6:P10000", col_names = TRUE)
Raw_Index_History <- Raw_Index_History[nrow(Raw_Index_History),]
Does anybody have any thoughts or advice? Thanks very much.
It would be easier to answer your question if you include an example.
Not knowing how your data looks like answers are likely going to be a bit vague.
Does your data contain NAs? If not it should be straight forward to remove the empty rows with
na.omit(Raw_Index_History)
It appears you also have control over the excel spreadsheet. So in case your data does contain NAs you could have some default value in your empty rows that will get overwritten as soon as a new data point is recorded. This will allow you to filter your dataframe accordingly.
Raw_Index_History[!grepl("place_holder", Raw_Index_History$column_with_placeholder),]
If you expect data in the spreadsheet to grow, you can specify only the columns to include, instead of a defined boundary.
Something like this ...
Raw_Index_History <- read_excel("RData.xlsx",
sheet = 1,
range = cell_cols("A:P"), # Only cols, no rows
col_names = TRUE)
Every time you run the code, R will pull in the data from columns between A:P up until the last populated row.
This will be a more elegant approach to your use case. (Consider what you'd do when your data crosses 10000 rows in the future)
This is probably a basic question, but why does R think my vector, which has a bunch of words in it, are numbers when I try to use these vectors as column names?
I imported a data set and it turns out the first row of data are the column headers that I want. The column headers that came with the data set are wrong ones. So I want to replace the column names. I figured this should be easy.
So what I did was I extracted the first row of data into a new object:
names <- data[1,]
Then I deleted the first row of data:
data <- data[-1,]
Then I tried to rename the column headers with the "names" object:
colnames(data) <- names
However, when I do this, instead of changing my column names to the words within the names object, it turns it into a bunch of numbers. I have no idea where these numbers come from.
Thanks
You need to actually show us the data, and the read.csv()/read.table() command you used to import.
If R thinks your numeric column is string, it sounds like that's because it wrongly includes the column name, i.e. you omitted header=TRUE in your read.csv()/read.table() import.
But show us your actual data and commands used.
I imported a set of data into RStudio containing 85 variables and 139 observations. All values are integers except for the last column which is blank and for some reason was imported alongside everything else in the .csv file I created from a .xls file.
As such, this last column is all NA values. The problem is that when I try to run any kind of analysis it seems to be reading that all values are NA values. Despite this, in the data window in RStudio everything seems to be fine. Are there solutions to this problem that don't involve the data? Is it almost certainly the data that's the problem?
It seems strange that when opening the file anywhere else and even viewing it in R
The most likely issue is that the file is being imported as all text rather than as numeric data. If all of the data is numeric you can just use colClasses="numeric" as an argument to the read.csv() function and that should import correctly. You could also change the data class once it is in R, or give colClasses a vector of different classes if you have a variety of different data types (logical, character, numeric etc.) in your file.
Edit
Seeing as colClasses is not working (it is hard to say why without looking at your data), you can try this:
MyDF<-data.frame(sapply(MyDF,FUN=as.numeric))
Where MyDF is your datafraome. That will change all of your columns to numeric. If you have some charcter/factor/logical values in there this may not work as expected. You might want to check your excel file/csv to see why it is importing a NA column. It could be that there is a cell with a space in it that is being pulled in and this is throwing things off. You could always try deleting that empty column and retrying your import.
If you want to omit your last column while reading the data itself, you can try the following code. In this example, I am assuming that your file has 5 columns and the 5th column has NA values. So, you want to skip reading 5th column in your data set.
data <- read.csv (fileName, ....) [,1:4]
or, if you want to use column names, you can use:
data <- read.csv (fileName, ....) [,c('col1','col2','col3','col4')]
This will read all the observations from selected columns within your data set.
Hope this helps.
If you are trying too find the mean and standard deviation you can use
Data<- mean( dataframe$colname , na.rm = TRUE)
Data1<- sd( dataframe$colname , na.rm = TRUE)
This will give u the answer after omitting the na values from the column