[R] read.delim problem with trailing spaces

[Michael Friendly]

I'm trying to read a comma delimited dataset that uses '.' for NA.  I 
found that if the last field on a line was a missing '.'
it was not read as NA, but just a '.', and the life variable was made a 
factor.  The data looks like this,

income,imr,region,oilexprt,imr80,gnp80,life
Afghanistan,75,400.0,4,0,185.0,.,37.5
Algeria,400,86.3,2,1,20.5,1920,50.7
Argentina,1191,59.6,1,0,40.8,2390,67.1
Australia,3426,26.7,4,0,12.5,9820,71.0
Austria,3350,23.7,3,0,14.8,10230,70.4
Bangladesh,100,124.3,4,0,139.0,120,.
Belgium,3346,17.0,3,0,11.2,12180,70.6
Benin,81,109.6,2,0,109.6,300,.
Bolivia,200,60.4,1,0,77.3,570,49.7
Brazil,425,170.0,1,0,84.0,2020,60.7
Britain,2503,17.5,3,0,12.6,7920,72.0
Burma,73,200.0,4,0,195.0,180,42.3
  ...

and I used
 > nations <- 
read.delim("~/sasuser/data/nations2.dat",na.strings=".",row.name=1,sep=",",header=TRUE)

> nations[1:10,]
            income   imr region oilexprt imr80 gnp80 life
Afghanistan     75 400.0      4        0 185.0    NA 37.5
Algeria        400  86.3      2        1  20.5  1920 50.7
Argentina     1191  59.6      1        0  40.8  2390 67.1
Australia     3426  26.7      4        0  12.5  9820 71.0
Austria       3350  23.7      3        0  14.8 10230 70.4
Bangladesh     100 124.3      4        0 139.0   120   .
Belgium       3346  17.0      3        0  11.2 12180 70.6
Benin           81 109.6      2        0 109.6   300   .
Bolivia        200  60.4      1        0  77.3   570 49.7
Brazil         425 170.0      1        0  84.0  2020 60.7
> summary(nations$life)
  .  27.0 31.6 32.0 32.6 34.5 35.0 36.0 36.7 36.9 37.1 37.2 37.5 38.5 38.8 40.5
   2    1    1    1    1    1    2    1    1    1    1    1    1    3    1    1
40.6 41.0 41.2 42.3 43.5 43.7 44.9 45.1 46.8 47.5 47.6 49.0 49.7 49.9 50.0 50.5
   1    6    1    4    1    1    1    1    1    3    1    3    1    1    2    1


After much hair-pulling, I discovered that the data lines for Bangladesh and Benin contained a trailing space after the '.'.  Removing those made the problem go away, but that shouldn't happen and I wonder if this is
still a potential problem for others.   I'm using R 1.8.1.

-Michael

-- 
Michael Friendly     Email: friendly at yorku.ca 
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
4700 Keele Street    http://www.math.yorku.ca/SCS/friendly.html
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