What does the "More Columns than Column Names" error mean?

Question

I'm trying to read in a .csv file from the IRS and it doesn't appear to be formatted in any weird way. I'm using the `read.table()` function, which I have used several times in the past but it isn't working this time; instead, I get this error: ``` data_0910<-read.table("/Users/blahblahblah/countyinflow0910.csv",header=T,stringsAsFactors=FALSE,colClasses="character") Error in read.table("/Users/blahblahblah/countyinflow0910.csv", : more columns than column names ``` Why is it doing this? For reference, the `.csv` files can be found at: http://www.irs.gov/uac/SOI-Tax-Stats-County-to-County-Migration-Data-Files (The ones I need are under the county to county migration .csv section - either inflow or outflow.)

Accepted Answer

It uses commas as separators. So you can either set `sep=","` or just use `read.csv`:

```
x <- read.csv(file="http://www.irs.gov/file_source/pub/irs-soi/countyinflow1011.csv")
dim(x)
## [1] 113593      9
```

The error is caused by spaces in some of the values, and unmatched quotes. There are no spaces in the header, so `read.table` thinks that there is one column. Then it thinks it sees multiple columns in some of the rows. For example, the first two lines (header and first row):

```
State_Code_Dest,County_Code_Dest,State_Code_Origin,County_Code_Origin,State_Abbrv,County_Name,Return_Num,Exmpt_Num,Aggr_AGI
00,000,96,000,US,Total Mig - US & For,6973489,12948316,303495582
```

And unmatched quotes, for example on line 1336 (row 1335) which will confuse `read.table` with the default `quote` argument (but not `read.csv`):

```
01,089,24,033,MD,Prince George's County,13,30,1040
```

What does the "More Columns than Column Names" error mean?

Solution

Problem