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Display vector or scalar fields as still images or movies

showf(V,BGMODE) displays the vector field(s) V as a still image or as a 
movie, using the background specified by BGMODE: 'rot','norm' etc. 
(See vec2scal for the list of available background modes). If no BGMODE 
specified, the out-of-plane component vz is used by default for 
3-components fields, and the 2D-norm for 2-components fields. 
Specify BGMODE='off' or '' for no background (white). 
showf(S), if S is a scalar field (or a set of scalar fields), displays 
the fields as a still image or as a movie. S is a structure (for a 
single field) or a structure array (for several fields) that can be 
obtained from vec2scal. 
During the movie, the following commands are available in live: 
    Space                   Enter/exit the 'pause' mode 
    '/' and '*'             Stretch/compress the colormap 
    '+' and '-'             Increase/decrease the vector arrow length 
    Right arrow, or 'n'     Next frame. 
    Left arrow,  or 'b'     Previous frame. 
    'g' or 'j'              Jump to a specified frame 
    Esc or 'x' or 'q' or Ctrl+C     Exit 
showf(V, 'PropertyName', PropertyValue, ...) specifies the property 
name / property value pairs (only the first letters of the PropertyName 
are required): 
  'Background' BGMODE : specifies the background BGMODE ('rot','norm', 
                        see vec2scal.) If BGMODE is the second input 
                        argument, it is not necessary to specify 
  'Spacing'   [NX NY] : displays 1 vector every NX (resp. NY) in the 
                        X (resp. Y) direction. 
  'Spacing'   N       : idem, with NX=NY=N. 
                        (by default, displays 32 vectors in each 
  'ScaleArrow' SA     : Specifies the scale for the vector arrows. 
                        SA is such that a vector of norm L (in 
                        vector units, e.g. m/s) has length SA*L 
                        (in units of space coordinates, e.g. mm). 
                        If SA<0, the arrows are not displayed. 
                        If not specified, or if SA = 0, a default value 
                        is automatically chosen. 
                        Use the keys '+' and '-' to modify this 
                        parameter during a movie. 
  'CLim':  [CMIN CMAX]: specifies the min and max of the colormap. 
           CMAX       : specifies the max of the colormap (0 or 
                        -CMAX is taken by default for the min) 
           'all', 0   : normalize the colormap using the min and 
                        max for all the scalar fields (by default). 
           'each', -1 : normalize the colormap using the min and 
                        max of each scalar field. 
  'Colorvec'  COL     : Color of the vector arrows. COL may be a 
                        string ('r', 'k' etc) or an array [R G B]. 
  'CMap': argcolormap : Specifies the colormap, where 'argcolormap' 
                        may be a string ('gray', 'jet' etc) or a 
                        m-by-3 matrix of real numbers between 0.0 and 
                        1.0. See the reference page for COLORMAP. 
  'Contour'   n       : Displays n contour lines 
  'Contourf'  n       : Displays n filled contour lines 
  'Streamline' [NX,NY]: display streamlines. The starting points of the 
                        streamlines are chosen on a uniform grid with 
                        spacing [NX,NY]. (NX=NY=16 by default) 
  'Loop':     -       : loop the movie (press 'esc' to exit) 
  'Backward': -       : plays backward 
  'Delay'     n       : waits n seconds between each frame 
  'Pause'     -       : directly enter in the 'pause' mode (press 
                        'space' to exit the pause mode) 
  'Title'     TIT     : string of the title. The following replacements 
                        are performed (default = '%s [#%i]'): 
                             '%n' : filename 
                             '%s' : directory name 
                             '%i' : field number 
                             '%t' : time in sec. (see getpivtime) 
                             '%t0' : time, with origin t(1)=0. 
  'savevideo', VID    : specify a video object VID to save the movie. 
                        The video object must be first initialized 
                        using videoWriter (see below). 
Some PropertyName/PropertyValue pairs work only for scalar fields: 
  'Contour3',  n        : Displays n 3D contour lines (n=8 by def.) 
  'Surf':     -         : 3-D shaded surface (see SURF) 
  'Surfc':    -         : 3-D shaded surface with a contour plot 
                          beneath the surface (see SURFC) 
  'Surfl':    -         : 3-D shaded surface with colormap-based 
                          lighting (see SURFL) 
  'Mesh':               : 3-D wireframe parametric surface (see MESH) 
  'Meshc':              : 3-D wireframe parametric surface with a 
                          contour plot beneath the surface (see MESCHC) 
  'hprofile', [y]       : adds horizontal profile(s) at height 
                          specified by y embedded in the figure 
  'vprofile', [x]       : adds vertical profile(s) at absisca 
                          specified by x embedded in the figure 
  'ResetCameraSettings' : refresh the camera angle, view etc. 
  'Command'  STR        : any Matlab string to be evaluated at each 
To save a movie in a file, there are two solutions: 
 1) Preferred solution: Using a videoWriter object 
      vid = VideoWriter('mymovie.avi'); 
      showf(v, ..., 'savevideo', vid); 
 2) Old solution: Using MOVIE2AVI (obsolete since Matlab 2016): 
      mov = showf(v, ...); 
      movie2avi(mov, 'mymovie.avi'); 
showf(FILENAME,...) is a shortcut for showf(loadvec(FILENAME),...) 
showf without input argument opens a dialog box for file selection. 
     showf *.vc7 
     showf('set.mat','loop','title','t = %t s'); 
     showf(v(1:10), 'norm', 'cmap', 'gray', 'colorvec', 'y'); 
     showf(s,'CLim',[0 14],'savevideo',vid); 
See Also
loadvec, vec2scal, operf, MOVIE, IMAGE, QUIVER, COLORMAP, 
convert3dto2df, MOVIE2AVI. 
Published output in the Help browser 
   showdemo showf 

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