draw_2D_shad_time(ncfile, values, varn)
  ncfile= file to use
  values=[vnamefs]~[dimvals]~[dimxvn]~[dimyvn]~[dimvfmt]~[colorbarvals]~[sminv],[smaxv]~[gridkind]~[figt]~
  [kindfig]~[reverse]~[timevals]~[close]
    [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 (-1, all the length, [beg]@[end] for an interval)
    [dimx/yvn]: name of the variables with the values of the final dimensions (x,y) ('WRFtime' for WRF times)
    [dimvfmt]=[dvs],[dvf],[Ndv],[ordv]: format of the values for the non-temporal axis (or 'auto')
      [dvs]: style of non-temporal 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)
      [dvf]: format of the labels at the x-axis ('auto' for '%5g')
      [Ndv]: Number of ticks at the x-axis ('auto' for 5)
      [ordv]: angle of orientation of ticks at the x-axis ('auto' for horizontal)
    [colorbarvals]=[colbarn],[fmtcolorbar],[orientation]
      [colorbarn]: name of the color bar
      [fmtcolorbar]: format of the numbers in the color bar 'C'-like ('auto' for %6g)
      [orientation]: orientation of the colorbar ('vertical' (default, by 'auto'), 'horizontal')
    [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)
    [gridkind]= [gridxk],[gridyk] kind of grid along x and y axis
      'data': size pixel along the given axis change according to the values along the axis
      'fixpixel': size pixel along the given axis does not change
    [figt]: title of the figure ('|' for spaces)
    [kindfig]: kind of figure
    [reverse]: '|' list of transformations to apply on the values
      * 'transpose': reverse the axes (x-->y, y-->x)
      * 'flip'@[x/y]: flip the axis x or y
    [timevals]: [timen]|[units]|[kind]|[tfmt]|[label]|[timeaxis] time labels characteristics
    [timen]; name of the time variable ('WRFtime' for WRF times)
    [units]; units string according to CF conventions ([tunits] since
      [YYYY]-[MM]-[DD] [[HH]:[MI]:[SS]], '!' for spaces)
    [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
    [label]; label at the graph ('!' for spaces)
    [close]: should figure be closed (finished)
  varn= [varsn] name of the variable to plot with shading