How to use the presto.ppgplot.pgsci function in presto

ppgplot.pgslw(width)
        # Choose the line color for the contourlines
        if isstr(color):
            ppgplot.pgsci(ppgplot_colors_[color])
        else:
            ppgplot.pgsci(color)
        # Construct the contours
        ppgplot.pgcont_s(z, len(contours), contours, rangex[0], \
                         rangey[0], rangex[1], rangey[1])  
        # Label the contours if requested
        if labels is not None:
            # Choose the line color for the contourlines
            if isstr(labels):
                ppgplot.pgsci(ppgplot_colors_[labels])
            else:
                ppgplot.pgsci(labels)
            for i in range(len(contours)):
                ppgplot.pgconl_s(z, contours[i], str(contours[i]),
                                 labelint, labelmin)

ppgplot.pgctab(pgpalette.l,pgpalette.r,pgpalette.g,pgpalette.b)
        # Construct the image
        ppgplot.pgimag_s(z, 0.0, 0.0, rangex[0], rangey[0], \
                         rangex[1], rangey[1])  
        reset_colors()
    if contours is not None:
        contours = Num.asarray(contours)
        # Choose the line style
        ppgplot.pgsls(line)
        # Choose the line width
        ppgplot.pgslw(width)
        # Choose the line color for the contourlines
        if isstr(color):
            ppgplot.pgsci(ppgplot_colors_[color])
        else:
            ppgplot.pgsci(color)
        # Construct the contours
        ppgplot.pgcont_s(z, len(contours), contours, rangex[0], \
                         rangey[0], rangex[1], rangey[1])  
        # Label the contours if requested
        if labels is not None:
            # Choose the line color for the contourlines
            if isstr(labels):
                ppgplot.pgsci(ppgplot_colors_[labels])
            else:
                ppgplot.pgsci(labels)
            for i in range(len(contours)):
                ppgplot.pgconl_s(z, contours[i], str(contours[i]),
                                 labelint, labelmin)

if x is None: x=Num.arange(len(y), dtype='f')
    else: x = Num.asarray(x)
    # Determine the scaling to use for the first axis
    if rangex is None: rangex=[x.min(), x.max()]
    if rangey is None:
        if noscale: rangey=[y.min(), y.max()]
        else: rangey=scalerange(y)
    # Prep the plotting device...
    if (not ppgplot_dev_prep_ and setup):
        prepplot(rangex, rangey, title, labx, laby, \
                 rangex2, rangey2, labx2, laby2, \
                 logx, logy, logx2, logy2, font, fontsize, \
                 id, aspect, ticks, panels, device=device)
    # Choose the line color
    if isstr(color):
        ppgplot.pgsci(ppgplot_colors_[color])
    else:
        ppgplot.pgsci(color)
    # Plot symbols (and errors) if requested
    if not symbol is None:
        ppgplot.pgpt(x, y, symbol)
    # Error bars
    if errx is not None:
        if not logx:
            errx = Num.asarray(errx)
            ppgplot.pgerrx(x+errx, x-errx, y, 1.0)
        else:
            errx = 10.0**Num.asarray(errx)
            ppgplot.pgerrx(Num.log10(10.0**x + errx),
                           Num.log10(10.0**x - errx), y, 1.0)
    if erry is not None:
        if not logy:

def resetdefaults():
    """
    resetdefaults():
        Reset global plotting variables to default values.
    """
    global ppgplot_font_, ppgplot_linestyle_, ppgplot_linewidth_, \
           ppgplot_color_, ppgplot_font_size_
    ppgplot.pgscf(ppgplot_font_)
    ppgplot.pgsls(ppgplot_linestyle_)
    ppgplot.pgslw(ppgplot_linewidth_)
    ppgplot.pgsci(ppgplot_colors_[ppgplot_color_])
    ppgplot.pgsch(ppgplot_font_size_)

# Determine the scaling to use for the first axis
    if rangex is None: rangex=[x.min(), x.max()]
    if rangey is None:
        if noscale: rangey=[y.min(), y.max()]
        else: rangey=scalerange(y)
    # Prep the plotting device...
    if (not ppgplot_dev_prep_ and setup):
        prepplot(rangex, rangey, title, labx, laby, \
                 rangex2, rangey2, labx2, laby2, \
                 logx, logy, logx2, logy2, font, fontsize, \
                 id, aspect, ticks, panels, device=device)
    # Choose the line color
    if isstr(color):
        ppgplot.pgsci(ppgplot_colors_[color])
    else:
        ppgplot.pgsci(color)
    # Plot symbols (and errors) if requested
    if not symbol is None:
        ppgplot.pgpt(x, y, symbol)
    # Error bars
    if errx is not None:
        if not logx:
            errx = Num.asarray(errx)
            ppgplot.pgerrx(x+errx, x-errx, y, 1.0)
        else:
            errx = 10.0**Num.asarray(errx)
            ppgplot.pgerrx(Num.log10(10.0**x + errx),
                           Num.log10(10.0**x - errx), y, 1.0)
    if erry is not None:
        if not logy:
            erry = Num.asarray(erry)
            ppgplot.pgerry(x, y+erry, y-erry, 1.0)

ppgplot.pgsls(line)
        # Choose the line width
        ppgplot.pgslw(width)
        # Choose the line color for the contourlines
        if isstr(color):
            ppgplot.pgsci(ppgplot_colors_[color])
        else:
            ppgplot.pgsci(color)
        # Construct the contours
        ppgplot.pgcont_s(z, len(contours), contours, rangex[0], \
                         rangey[0], rangex[1], rangey[1])  
        # Label the contours if requested
        if labels is not None:
            # Choose the line color for the contourlines
            if isstr(labels):
                ppgplot.pgsci(ppgplot_colors_[labels])
            else:
                ppgplot.pgsci(labels)
            for i in range(len(contours)):
                ppgplot.pgconl_s(z, contours[i], str(contours[i]),
                                 labelint, labelmin)