def graphPlot(workspace, again, tokens):
    """Function for plotting graphs in 2D and 3D space

    2D graphs are plotted for expression in one variable and equations in two variables. 3D graphs are plotted for expressions in two variables and equations in three variables.

    Arguments:
        workspace {QtWidgets.QWidget} -- main layout

    Returns:
        graphVars {list} -- variables to be plotted on the graph
        func {numpy.array(2D)/function(3D)} -- equation converted to compatible data type for plotting
        variables {list} -- variables in given equation
        again {bool} -- True when an equation can be plotted in 2D and 3D both else False

    Note:
        The func obtained from graphPlot() function is of different type for 2D and 3D plots. For 2D, func is a numpy array, and for 3D, func is a function.
    """
    if tokens is None:
        axisRange = workspace.axisRange
        tokens = workspace.eqToks[-1]
    else:
        axisRange = [10, 10, 10, 30]
    eqType = getTokensType(tokens)
    LHStok, RHStok = getLHSandRHS(tokens)
    variables = sorted(getVariables(LHStok, RHStok))
    dim = len(variables)
    if (dim == 1) or ((dim == 2) and eqType == "equation"):
        if again:
            variables.append('f(' + variables[0] + ')')
            graphVars, func = plotIn3D(LHStok, RHStok, variables, axisRange)
        else:
            graphVars, func = plotIn2D(LHStok, RHStok, variables, axisRange)
        if dim == 1:
            variables.append('f(' + variables[0] + ')')
    elif (dim == 2 and eqType == "expression") or ((dim == 3) and eqType == "equation"):
        graphVars, func = plotIn3D(LHStok, RHStok, variables, axisRange)
        if dim == 2:
            variables.append('f(' + variables[0] + ',' + variables[1] + ')')
    else:
        return [], None, None
    return graphVars, func, variables