draw_2Dshad_map(ncfile, values, varn)
plotting a shadow field with a background map
  ncfile= file to use
  values=[vnamemap];[vnamefs];[dimvals];[dimxvn];[dimyvn];[dimxyfmt];
      [colorbarvals];[sminv],[smaxv];[figt];[kindfig];[mapkind];[mapv];[close]
    [vnamemap]: Name of the variable to be used for map
    [vnamefs]: Name in the figure of the variable to be shaded
    [dimvals]: ',' list of [dimname]|[value] telling at which dimension of the
        variable a given value is required:
      * [integer]: which value of the dimension
      * -1: all along the dimension
      * -9: last value of the dimension
      * [beg]@[end]@[inc] slice from [beg] to [end] every [inc]
      * NOTE, no dim name all the dimension size
    [dimx/yvn]: name of the variables with the values of the final dimensions (x,y)
    [dimxyfmt]=[dxs],[dxf],[Ndx],[ordx],[dys],[dyf],[Ndy],[ordx]: format of the values at each axis (or 'auto')
      [dxs]: style of x-axis ('auto' for 'pretty')
        'Nfix', values computed at even 'Ndx'
        'Vfix', values computed at even 'Ndx' increments
        'pretty', values computed following aprox. 'Ndx' at 'pretty' intervals (2.,2.5,4,5,10)
      [dxf]: format of the labels at the x-axis ('auto' for '%5g')
      [Ndx]: Number of ticks at the x-axis ('auto' for 5)
      [ordx]: angle of orientation of ticks at the x-axis ('auto' for horizontal)
      [dys]: style of y-axis ('auto' for 'pretty')
      [dyf]: format of the labels at the y-axis ('auto' for '%5g')
      [Ndy]: Number of ticks at the y-axis ('auto' for 5)
      [ordy]: angle of orientation of ticks at the y-axis ('auto' for horizontal)
    [colorbarvals]=[colbarn]#[fmtcolorbar]#[orientation]#[colorbarticks]
      [colorbarn]: name of the color bar for the values to plot
      [fmtcolorbar]: format of the numbers in the color bar 'C'-like ('auto' for %6g)
      [orientation]: orientation of the colorbar ('vertical' (default, by 'auto'), 'horizontal')
      [colorbarticks]: kind of colorbarticks
        'direct': direct values
        'time'@[units]|[kind]|[tfmt]|[label] time labels characteristics
          [units]: units string according to CF conventions ([tunits] since
            [YYYY]-[MM]-[DD] [[HH]:[MI]:[SS]], '!' for spaces),
            'auto' for minutes!since!1949-12-01!00:00:00
          [kind]: kind of output
            'Nval': according to a given number of values as 'Nval',[Nval]
            'exct': according to an exact time unit as 'exct',[tunit];
              tunit= [Nunits],[tu]; [tu]= 'c': centuries, 'y': year, 'm': month,
                'w': week, 'd': day, 'h': hour, 'i': minute, 's': second,
                'l': milisecond
          [tfmt]: desired format (combination of 'C'-style values and LaTeX)
          [label]: label at the graph ('!' for spaces, combination of 'C'-style
            values and LaTeX)
    [smin/axv]: minimum and maximum value for the shading or:
      'Srange': for full range
      'Saroundmean@val': for mean-xtrm,mean+xtrm where xtrm = np.min(mean-min@val,max@val-mean)
      'Saroundminmax@val': for min*val,max*val
      'Saroundpercentile@val': for median-xtrm,median+xtrm where xtrm = np.min(median-percentile_(val),
        percentile_(100-val)-median)
      'Smean@val': for -xtrm,xtrm where xtrm = np.min(mean-min*@val,max*@val-mean)
      'Smedian@val': for -xtrm,xtrm where xtrm = np.min(median-min@val,max@val-median)
      'Spercentile@val': for -xtrm,xtrm where xtrm = np.min(median-percentile_(val),
        percentile_(100-val)-median)
    [figt]: title of the figure ('|' for spaces)
    [kindfig]: kind of file for the figure output (ps, eps, png, pdf, ...)
    [mapfmt] = [cbarmap]|[mapkind]|[lonlatbox] values for the map
      cbarmap: name of the colorbar for the map
      mapkind: kind of map to use in the plot
        'direct': values are they come
        'shadow',[pos],[enhance]: pseudo-shadding from a given location of the sun
          [pos]: 'N', 'NW'
          [enhance]: enhance factor for the shading ('auto' for 1./5.)
      lonlatbox: [lonSW],[latSW],[lonNE],[latNE] to plot only a lon,lat box
        'full': for the whole domain
    [mapv]: map characteristics: [proj],[res]
        see full documentation: http://matplotlib.org/basemap/
        [proj]: projection
          * 'cyl', cilindric
          * 'lcc', lambert conformal
        [res]: resolution:
          * 'c', crude
          * 'l', low
          * 'i', intermediate
          * 'h', high
          * 'f', full
    [close]: Whether figure should be finished or not
  varn= [varsn] name of the variable to plot with shading