def linestylecb(i,a=5,b=3):
    '''
        version of linestyle function with colourblind colour scheme

        returns linetyle, marker, color (see example)

        Parameters
        ----------
        i : integer
        Number of linestyle combination - there are many....
        a : integer
        Spacing of marks.  The default is 5.
        b : integer
        Modulation in case of plotting many nearby lines.  The default
        is 3.

        Examples
        --------

        >>> plot(x,sin(x),ls=linestyle(7)[0], marker=linestyle(7)[1], \
                 color=linestyle(7)[2],markevery=linestyle(7)[3])


        (c) 2014 FH
        '''

    lines=['-','--','-.',':']
    points=['v','^','<','>','1','2','3','4','s','p','*','h','H','+','x','D','d','o']
    colors=['b','g','r','c','m','k']
    col=colourblind(i)
    style=lines[sc.mod(i,4)]
    point=points[sc.mod(i,18)]
    mark_i    = a+sc.mod(i,b)
    return style,point,col,mark_i
version of linestyle function with colourblind colour scheme

        returns linetyle, marker, color (see example)

        Parameters
        ----------
        i : integer
        Number of linestyle combination - there are many....
        a : integer
        Spacing of marks.  The default is 5.
        b : integer
        Modulation in case of plotting many nearby lines.  The default
        is 3.

        Examples
        --------

        >>> plot(x,sin(x),ls=linestyle(7)[0], marker=linestyle(7)[1], \
                 color=linestyle(7)[2],markevery=linestyle(7)[3])


        (c) 2014 FH