Description Usage Arguments Details Value Missing and non- values Ties Author(s) See Also
Gets the rank of each row (column) of a matrix.
1 2 |
x |
A |
ties.method |
A |
preserveShape |
A |
... |
Not used. |
The row ranks of x are collected as rows
of the result matrix.
The column ranks of x are collected as rows
if preserveShape = FALSE, otherwise as columns.
The implementation is optimized for both speed and memory.
To avoid coercing to doubles (and hence memory allocation), there
is a unique implementation for integer matrices.
It is more memory efficient to do
colRanks(x, preserveShape=TRUE) than
t(colRanks(x, preserveShape=FALSE)).
Currently, colRanks(x) is just rowRanks(t(x)).
Any names of x are ignored and absent in the result.
An integer matrix is returned.
The rowRanks() function always returns an NxK matrix,
where N (K) is the number of rows (columns) whose ranks are calculated.
The colRanks() function returns an NxK matrix,
if preserveShape = TRUE, otherwise a KxN matrix.
These are ranked as NA, as with na.last="keep"
in the rank() function.
When some values are equal ("ties"), argument ties.method
specifies what their ranks should be.
If ties.method is "max", ties
are ranked as the maximum value.
If ties.method is "average", ties are ranked
by their average.
If ties.method is "max" ("min"), ties
are ranked as the maximum (minimum) value.
If ties.method is "average", ties are ranked
by their average.
For further details, see rank().
Hector Corrada Bravo and Harris Jaffee.
Peter Langfelder for adding 'ties.method' support.
Henrik Bengtsson adapted the original native implementation
of rowRanks() from Robert Gentleman's rowQ()
in the Biobase package.
rank().
For developers, see also Section 'Utility functions' in
'Writing R Extensions manual', particularly the native functions
R_qsort_I() and R_qsort_int_I().
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.