Limited count of column in XLSX file - r

I should generate a big excel spreadsheet with XLConnect. I am filling each column in this spreadscheet with my calculation and at the end I am writing my calculation in the spreadscheet:
writeWorksheetToFile(file=FileName,mtr,startRow=1,startCol=strcol,sheet="Sheet1",header=FALSE,rownames=FALSE)
but if I a open the excel file I can only see until AMJ coloumn. Is there a way, that I see my total column or the count of columns in XLSX file is limited?

I am not sure Kaja about this, because I use a convenience wrapper for XLConnect, but all I need to provide as arguments are the object I want to print to file (for you, "mtr") and the filename, such as perhaps "mtr.print.xlsx".
Why do you need to specify the startRow? Also, perhaps your startCol argument only leaves the AMJ column? Have you tried omitting it?
In short, only all the R object and the filename and see what happens.

Related

When I upload my excel file to R, the column titles are in the rows and the data seems all jumbled. How do I fix this?

hi literally day one new coder
On the excel sheet, my data looks organized, but when I upload my file to R, it's not able to read the excel properly and the column headers are in the rows and the data seems randomized.
So far I have tried:
library(readxl)
dataset <-read_excel("pathname")
View(dataset)
Also tried:
dataset <-read_excel("pathname", sheet=1, colNames=TRUE)
Also tried to use the package openxlsx
but nothing is giving me the correct, organized data set.
I tried formatting my Excel to a CSV file, and the CSV file looks exactly like the data that shows up on R (both are messed up).
How should I approach this problem?
I deal with importing .xlsx into R frequently. It can be challenging due to the flexibility of the excel platform. I generally use readxl::read_xlsx() to fetch data from .xlsx files. My suggestions:
First, specify exactly the data you want to import with the range argument.
A cell range to read from, as described in cell-specification. Includes typical Excel
ranges like "B3:D87", possibly including the sheet name like "Budget!B2:G14"
Second, if there are there merged cells or other formatting challenges in column headers, I resort to setting col_names = FALSE. And supplying clean names after import with names(df) <- c("first_col", "second_col")
Third, if there are merged cells elsewhere in the spreadsheet I generally I resort to "fixing" them in excel (not ideal but easier for my use case), however, others may have suggestions on a programmatic fix.
It may be helpful to provide a screenshot of your spreadsheet.

R misreading csv files after modifications on Excel

This is more of a curiosity.
Sometimes I modify csv files from Excel rather than R (suppose I manage to find a missing piece of info and I type it in the csv file), of course maintaining commas and quotes as they were.
Every time I do this, R becomes unable to read the csv file, i.e. it imports a single column as it appears on Excel, rather than separating the values (no options like sep= or quote= change this).
Does anyone know why this happens?
Thanks a lot
An example
This was readable:
state,"city","county"
AK,"Anchorage",""
AK,"Haines",""
AK,"Juneau","Juneau"
After adding the missing info under "county", R fails to import it as a data frame, reading it instead as a single vector.
state,"city","county"
AK,"Anchorage","Anchorage"
AK,"Haines","Haines"
AK,"Juneau","Juneau"
Edit:
I'm just running the basic read.csv
df <- read.csv("C:/directory/df.csv")

How do I get EXCEL to interpret character variable without scientific notation in R using fwrite?

I have a relatively simple issue when writing out in R with fwrite from the data.table package I am getting a character vector interpreted as scientific notation by Excel. You can run the following code to create the data issue:
#create example
samp = data.table(id = c("7E39", "7G32","5D99999"))
fwrite(samp,"test.csv",row.names = F)
When you read this back into R you get values back no problem if you have scinote disable. My less code capable colleagues work with the csv directly in excel and they see this:
They can attempt to change the variable to text but excel then interprets all the zeros. I want them to see the original "7E39" from the data table created. Any ideas how to avoid this issue?
PS: I'm working with millions of rows so write.csv is not really an option
EDIT:
One workaround I've found is to just create a mock variable with quotes:
samp = data.table(id = c("7E39", "7G32","5D99999"))[,id2:=shQuote(id)]
I prefer a tidyr solution (pun intended), as I hate unnecessary columns
EDIT2:
Following R2Evan's solution I adapted it to data table with the following (factoring another numerical column, to see if any changes occured):
#create example
samp = data.table(id = c("7E39", "7G32","5D99999"))[,second_var:=c(1,2,3)]
fwrite(samp[,id:=sprintf("=%s", shQuote(id))],
"foo.csv", row.names=FALSE)
It's a kludge, and dang-it for Excel to force this (I've dealt with it before).
write.csv(data.frame(id=sprintf("=%s", shQuote(c("7E39", "7G32","5D99999")))),
"foo.csv", row.names=FALSE)
This is forcing Excel to consider that column a formula, and interpret it as such. You'll see that in Excel, it is a literal formula that assigns a static string.
This is obviously not portable and prone to all sorts of problems, but that is Excel's way in this regard.
(BTW: I used write.csv here, but frankly it doesn't matter which function you use, as long as it passes the string through.)
Another option, but one that your consumers will need to do, not you.
If you export the file "as is", meaning the cell content is just "7E39", then an auto-import within Excel will always try to be smart about that cell's content. However, you can manually import the data.
Using Excel 2016 (32bit, on win10_64bit, if it matters):
Open Excel (first), have an (optionally empty) worksheet already open
On the ribbon: Data > Get External Data > From Text
Navigate to the appropriate file (CSV)
Select "Delimited" (file type), click Next, select "Comma" (and optionally deselect any others that may default to selected), Next
Click on the specific column(s) and set the "Default data format" to "Text" (this will need to be done for any/all columns where this is a problem). Multiple columns can be Shift-selected (for a range of columns), but not Ctrl-selected. Finish.
Choose the top-left cell to import/paste the data (or a new worksheet)
Select Properties..., and deselect "Save query definition". Without this step, the data is considered a query into an external data source, which may not be a problem but makes some things a little annoying. (For example, try to highlight all data and delete it ... Excel really wants to make sure you know what you're doing there.)
This method provides a portable solution. It "punishes" the Excel users, but anybody/anything else will still be able to consume the files directly without change. The biggest disadvantage with this method is that you won't know if somebody loads it incorrectly unless/until they get odd results when the try to use the data and some fields are silently converted.

Large csv file fails to fully read in to R data.frame

I am trying to load a fairly large csv file into R. It has about 50 columns and 2million row.
My code is pretty basic, and I have used it to open files before but none this large.
mydata <- read.csv('file.csv', header = FALSE, sep=",", stringsAsFactors = FALSE)
The result is that it reads in the data but stops after 1080000 rows or so. This is roughly where excel stops as well. Is their way to get R to read the whole file in? Why is it stopping around half way.
Update: (11/30/14)
After speaking with the provider of the data it was discovered that they may have been some corruption issue with the file. A new file was provided which also is smaller and loads into R easily.
As, "read.csv()" read up to 1080000 rows, "fread" from library(data.table) should read it with ease. If not, there exists two other options, either try with library(h20) or with "fread" you can use select option to read required columns (or read in two halves, do some cleaning and can merge them back).
You can try using read.table and include the parameter colClasses to specify the type of the individual columns.
With your current code, R will read all data first as strings and then check for each column if it is convertible e. g. to a numeric type, which needs more memory than reading right away as numeric. colClasses will also allow you to ignore columns you might not need.

Load Excel file to R while setting column equal to a factor

I have an Excel file that I am trying to load into R using the odbcConnectExcel and sqlQuery commands from RODBC package. One of the columns has numerical values with plus or minus signs, such as '5+ or '3-. However, if i do something like,
conn <- odbcConnectExcel("file.xls")
sqlQuery(conn, "SELECT * FROM `Sheet1$`")
then the column with the plus and minus signs will be returned as a numerical column with those symbols stripped. Is there a way to have this column read in as a factor in which the signs are maintained? I would prefer to not have to convert the file to another format first.
Thanks.
Data like this becomes a factor if you use the xlsReadWrite (http://www.swissr.org/software/xlsreadwrite) package to read the file:
library(xlsReadWrite)
x <- read.xls(file="file.xls")
However, note that you need to do something more than just install.packages("xlsReadWrite") to get this package to run. You need another file or so, I forgot.
This doesn't directly address your question, but hopefully it will help:
This is the best summary of options for connecting to Excel that I have seen: Export Data Frames To Multi-worksheet Excel File. While it deals generally with exporting, importing is also possible with most of these approaches.
My favorite is actually the RDCOMClient because it provides total control over Excel as an application.

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