Dear all,
I work with SAS 9.4.
Now I am trying to apply proc gproject to covert WGS84-coordinates to a particular Lambert-projection.
And keep getting unsatisfactory results.
My test coordinates are:
long=13.84 ; lat=49.77
The correct answer should be
XOK=272304.68; YOK =2212578.11
My code is
data tmp; long=13.84 ; lat=49.77; XOK=272304.68; YOK =2212578.11; run;
proc gproject data=tmp out=tmp1 degrees latlong from="+proj=longlat +datum=WGS84"
to = "+proj=lcc +lat_1=40 +lat_2=60 +lat_0=30 +lon_0=10 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"; id ; run;
proc print data=tmp1; run;
X | Y | long | lat | XOK | YOK |
316986.13 | 2908828.39 | 13.84 | 49.77 | 272304.68 | 2212578.11 |
which is obviously wrong
Then I tried it in R:
require(rgdal)
require(spatstat)
xy <- c(13.84, 49.77)
sp1 <- SpatialPoints(coord=matrix(xy, ncol=2))
proj4string(sp1) <- CRS("+proj=longlat +datum=WGS84")
spTransform(sp1, CRS=CRS("+proj=lcc +lat_1=40 +lat_2=60 +lat_0=30 +lon_0=10 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"))
which gives the correct values:
SpatialPoints:
coords.x1 coords.x2
[1,] 272304.7 2212578
Does Sas use some kind of a deviant formula for Lambert transformations?
Thanks in advance
It appears there was a bug in version 9.4, and it appears that bug is fixed in the 9.4 maintenance 4 (9.4m4) release.
Here's the output when I run your program at 9.4m4 ...
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