2D functions

Class Realfunction2d

Generic real 2D function class (real function of two real arguments). Polymorphic input and output is provided for pointers to objects of this class. Polymorphic data format: 
function_type
data_for_that_function
The data format depends on the type of function chosen. Names (for identifying the function type) and formats are defined below.

Class: Realfunction2d_1dproduct

Product of two 1D functions of each of the arguments. Name: 1dproduct Data format: 
function_of_x
function_of_y
Data is a pair of Realfunction1ds.

Class: Realfunction2d_1dinterp_1

Set of functions of the second argument, using the first argument to interpolate between the functions. Name: 1dinterp_1 Data format: 
number_of_functions_of_y
For each:
   x f(y)
Each f(y)is a Realfunction1d.

Class: Realfunction2d_1dinterp_2

Set of functions of the first argument, using the second argument to interpolate between the functions. Name: 1dinterp_2 Data format: 
number_of_functions_of_x
For each:
   y f(x)
Each f(x)is a Realfunction1d.

Class: Realfunction2d_table

2D table. Name: table. Data is an array of pairs of doubles modelling f(x) as piecewise linear. The function evaluated is the linear interpolation (or extrapolation). Data format: 
nx ny	(dimensions of table)
For each x:
   xi   (x-ordinates)
For each y:
   yj   (y-ordinates)
For each x:
   For each y:
      fi,j   (function values)

Class: Realfunction2d_table_bipoly

2D table with polynomial interpolation. Name: table_bipoly. Data is an array of pairs of doubles modelling f(x) as piecewise polynomial. The function evaluated is the polynomial interpolation (or extrapolation). Data format: As `Table1d', plus 
xorder yorder (order of polynomials used to interpolate in x and y)
xfirst (1/0 for interpolation in x first/second)

Class: Realfunction2d_sum

Sum of a set of 2D functions. Name: sum. Data: 
number_of_functions
For each:
   fi                (Realfunction2d)
The function calculated is the sum of the fi.

Class: Realfunction2d_product

Product of a set of 2D functions. Name: product. Data: 
number_of_functions
For each:
   fi                (Realfunction2d)
The function calculated is the product of the fi.

Class: Realfunction2d_offset

General 2D function offset by a constant amount. Name: offset. Data: 
x0 y0	(offset in x and y direction)
f	(Realfunction2d)
The function calculated is f(x-x0,y-y0).

Class: Realfunction2d_map

General 2D function with general mappings applied to arguments and result. Name: map. Data: 
xmap ymap	(mapping functions for x and y ordinates)
fmap		(mapping function for result)
f		(Realfunction2d)
The mapping functions are all Realfunction1ds. The function calculated is fmap{f[xmap(x),ymap(y)]}. This is a fairly general form, but is particularly useful for changing units or scalings.