def boxplot_single_factor(df='dataframe', column_names=None, grid=False, ar=(0, 0), axtickfontsize=9,
                          axtickfontname='Arial', dim=(6, 4), show=False, figtype='png', figname='boxplot', r=300,
                          ylm=None, box_line_style='-', box_line_width=1, box_line_color='b', med_line_style='-',
                          med_line_width=1, med_line_color='g', whisk_line_color='b', cap_color='b',
                          add_sign_symbol=False, symb_dist=None, sign_symbol_opts={'symbol': '*', 'fontsize': 8 },
                          pv=None, notch=False, outliers=True, fill_box_color=True, dotplot=False, dotsize=6,
                          colordot=['#101820ff'], valphadot=1, markerdot='o', theme=None):
    if theme == 'dark':
        general.dark_bg()
    plt.subplots()
    if column_names:
        xbar = column_names
    else:
        xbar = list(df.columns)
        # rot is x axis rotation
    other_args = {'grid': grid, 'rot': ar[0], 'fontsize': axtickfontsize, 'notch':notch, 'showfliers':outliers,
                  'figsize': dim, 'patch_artist': fill_box_color}
    color_args = {'medians': med_line_color, 'boxes': box_line_color, 'whiskers': whisk_line_color,
                  'caps': cap_color}
    medianprops_args = {'linestyle': med_line_style, 'linewidth': med_line_width}
    boxprops_args = {'linestyle': box_line_style, 'linewidth': box_line_width}

    if isinstance(column_names, list):
        df.boxplot(column=column_names, **other_args, boxprops=boxprops_args, medianprops=medianprops_args,
                   color=color_args)
    else:
        df.boxplot(**other_args, boxprops=boxprops_args, color=color_args, medianprops=medianprops_args)

    # ylm must be tuple of start, end, interval
    if ylm:
        plt.ylim(bottom=ylm[0], top=ylm[1])
        plt.yticks(np.arange(ylm[0], ylm[1], ylm[2]), fontsize=axtickfontsize, fontname=axtickfontname)
    plt.yticks(fontsize=axtickfontsize, rotation=ar[1], fontname=axtickfontname)

    color_list_dot = colordot
    if len(color_list_dot) == 1:
        color_list_dot = colordot * len(xbar)
    # checked for unstacked data
    if dotplot:
        for cols in range(len(xbar)):
            plt.scatter(
                x=np.linspace(xbar[cols] - bw / 2, xbar[cols] + bw / 2, int(bar_counts[cols])),
                y=df[df.columns[cols]].dropna(), s=dotsize, color=color_list_dot[cols], zorder=10, alpha=valphadot,
                marker=markerdot)

    size_factor_to_start_line = max(df.max()) / 20
    if add_sign_symbol:
        # p and symb_dist should be dict
        if isinstance(pv, dict):
            for k, v in pv.items():
                if isinstance(symb_dist, dict):
                    if k not in symb_dist:
                        symb_dist[k] = 0
                    y_pos = df[k].max() + size_factor_to_start_line + symb_dist[k]
                else:
                    y_pos = df[k].max() + size_factor_to_start_line

                if y_pos > 0 and v <= 0.05:
                    pv_symb = general.pvalue_symbol(v, sign_symbol_opts['symbol'])
                    if pv_symb:
                        plt.annotate(pv_symb, xy=((xbar.index(k))+1, y_pos),
                                     fontsize=sign_symbol_opts['fontsize'],
                                     ha="center")

    general.get_figure(show, r, figtype, figname, theme)