extract a subset of the spectra in a colorSpec object.
The subset can be specified by indexes, by a logical vector, or by a regular expression matching the
specnames
Usage
## S3 method for class 'colorSpec':
subset( x, subset, ... )
Arguments
x
a colorSpec object
subset
an integer vector, a logical vector, or a regular expression
...
additional arguments ignored
Value
subset(x) returns a colorSpec object with the same organization as x.
Exception: if the organization of x is 'vector' and the subset is empty,
then the returned object is a matrix with 0 columns.
Details
If subset is an integer vector, each integer must be between 1 and M,
where M the number of spectra in x.
No duplicates are allowed.
The number of spectra returned is equal to length(subset).
It is OK for the length to be 0, in which case the function returns the empty subset.
If subset is a logical vector, its length must be equal to M.
The number of spectra returned is equal to the number of TRUEs in subset.
If subset is a regular expression, the number of spectra returned is equal to
the number of specnames(x) matched by the expression.
tritanope = subset( lms2000.1nm, 1:2 ) # keep long and medium cone fundamentals, but drop the shortsml2000.1nm = subset( lms2000.1nm, 3:1 ) # reorder from short to long