def append_dataset(path, data, index=None, type='d', shape=None):
    """Append data to dataset.

    Args:
        path(str): Path to dataset relative to the current persistence context root.
        data(number or array or list): name of each column.
        index(int or list, optional): if set then add the data in a specific position in the dataset.
                If integer is the index in an array (data must be 1 order lower than dataset)
                If a list, specifies the full coordinate for multidimensional datasets.
        type(str, optional): array type 'b' = byte, 'h' = short, 'i' = int, 'l' = long,  'f' = float,
                              'd' = double, 'c' = char, 's' = String,  'o' = Object
                   default: 'd' (convert data to array of doubles)
        shape(list, optional): only valid if index is a list, provides the shape of the data array.
                In this case data must be a flattened one-dimensional array.
    Returns:
        None
    """
    data = to_array(data, type)
    
    if index is None:
        get_context().dataManager.appendItem(path, data)
    else:
        if is_list(index):
            if shape is None:
                shape = [len(index)]
            get_context().dataManager.setItem(path, data, index, shape)
        else:
            get_context().dataManager.setItem(path, data, index)
            

path = "data/data4d"
data3d = [ [ [1,2,3,4,5],  [2,3,4,5,6],  [3,4,5,6,7],  [4,5,6,7,8]],
            [ [2,2,3,4,5],  [3,3,4,5,6],  [5,4,5,6,7],  [7,5,6,7,8]],
            [ [3,2,3,4,5],  [4,3,4,5,6],  [6,4,5,6,7],  [8,5,6,7,8]] ]

plot(data3d)

data = flatten(to_array(data3d,'i))



#save_dataset(path, data4d)
create_dataset(path, 'i',  dimensions = [2, 3, 4, 5])
append_dataset(path, data, index = [0,0,0,0], type = 'i', shape=[1, 3, 4, 5])