Managing continuous data
Continuous data can be imported from tab-delimited tables in ASCII text files, or entered into the spreadsheet editor (Character Matrix Editor). Values entered can be negative or positive, and include exponential notation (e.g., "1.3e-6").A continuous data matrix can have an extra dimension, in that the entry for each cell of the matrix (character state in a taxon) can have more than one number. These separate numbers are called "items", and thus a character matrix can be described as having three dimensions, characters X taxa X items. The first item could be the mean; the second the variance. Or, there could be 3 items, x, y and z, representing coordinates of a landmark in space. To manage items, use the Utilities submenu of the Matrix menu.
The following can be applied to all or the selected portions of a continuous matrix in the Character Matrix Editor. These are available under the Alter/Transform submenu of the Matrix menu:
- Fill — fills the cells with the current "paint" state
- Standardize — transforms the characters to have mean 0 and variance 1.
- Random fill — fills the cells with randomly generated states, with given mean and variance.
- Add random noise — adds random noise to the entries.
- Add constant — adds a specified constant to all entries.
- Multiply constant — multiplies all entries by a specified constant.
Other options may appear. You can also apply the other editing tools described for character matrices.