STK_DATAFRAME constructs a dataframe object CALL: D = stk_dataframe (X) constructs a dataframe object from X. If X is a plain numeric array, then D is dataframe without row or column names. If X already is an stk_dataframe object, row names and column names are preserved when they exist. CALL: D = stk_dataframe (X, COLNAMES) allows to specify column names for the dataframe D. Row names from X are preserved when they exist. If COLNAMES is empty ([]), this is equivalent to D = stk_dataframe (X); in particular, if X has column names, then D inherits from them. If COLNAMES is an empty cell({}), the resulting dataframe has no column names. CALL: D = stk_dataframe (X, COLNAMES, ROWNAMES) allows to specify row names as well. If ROWNAMES is empty ([]), this is equivalent to D = stk_dataframe (X, COLNAMES); in particular, if X has row names, then D inherits from them. If ROWNAMES is an empty cell({}), the resulting dataframe has no row names. NOTE: How to extract the underlying array It is sometimes useful to extract from an stk_dataframe object the underlying numerical (double precision) array. This can be achieved either using the 'data' field of the object: x1 = x.data; % x1 is a numerical array or using a cast to double: x2 = double (x); % x2 is a numerical array too, identical to x1 Note that the second syntax remains valid even if x is a numerical array (single, double, uint8...) instead of an stk_dataframe object. See also: stk_factorialdesign, stk_hrect
Package: stk