castToMatrix: Cast a data.table to a matrix
In oliviermfmartin/HelpingHand: A helping hand

A wrap-around the dcast function that returns a matrix instead of a data.table

1	castToMatrix(data, formula, value.var, fun.aggregate, fill = NA, ...)

`data`	A `data.table`.
`formula`	A formula of the form LHS ~ RHS to cast, see Details.
`value.var`	Name of the column whose values will be filled to cast. Function `guess()` tries to, well, guess this column automatically, if none is provided. Cast multiple `value.var` columns simultaneously by passing their names as a `character` vector. See Examples.
`fun.aggregate`	Should the data be aggregated before casting? If the formula doesn't identify a single observation for each cell, then aggregation defaults to `length` with a message. To use multiple aggregation functions, pass a `list`; see Examples.
`fill`	Value with which to fill missing cells. If `fun.aggregate` is present, takes the value by applying the function on a 0-length vector.
`...`	Any other arguments that may be passed to the aggregating function.