[R] variables - data-structure

[Helmut Kudrnovsky]

dear R-friends,

i`ve got a large dataset of  vegetation-samples with about 500 
variables(=species) in the following format:

1 spec1
1 spec23
1 spec54
1 spec63
2 spec1
2 spec2
2 spec253
2 spec300
2 spec423
3 spec20
3 spec88
3 spec121
3 spec200
3 spec450
.
.

this means:  sample 1 (grassland) with the species (=spec) 1, 23, 54, 63

is it possible to get a following data-structure for further analysis?

		1	2	3	......
spec1		1	1	0
spec2		0	1	0
spec3
...
spec253	0	1	0
...
spec450	0	0	1

with thanks from the snowy tirol
helli