| 
            plvect
          ( | u , | 
| v , | |
| nx , | |
| ny , | |
| scale , | |
| pltr , | |
| pltr_data ); | 
      Draws a plot of vector data contained in the matrices
      
        (.
      The scaling factor for the vectors is given by
      u[nx][ny],v[nx][ny])
      scalepltrpltr_dataplsvect.
    
u, v
          (PLFLT_MATRIXA pair of matrices containing the x and y components of the vector data to be plotted.
nx, ny
          (PLINT
            Dimensions of the matrices
            uv
scale
          (PLFLT
            Parameter to control the scaling factor of the vectors for plotting.
            If scale = 0
            scale < 0-.
            If scale
            scale > 0scale
pltr
          (PLTRANSFORM_callback A callback function that defines the transformation
	  between the zero-based indices of the matrices
	  uv
For the C case, transformation functions are provided
	  in the PLplot library: pltr0 for the identity mapping, and pltr1
	  and pltr2 for arbitrary mappings respectively defined by vectors and
	  matrices.  In addition, C callback routines for the transformation can
	  be supplied by the user such as the mypltr function
	  in examples/c/x09c.c which provides a general
	  linear transformation between index coordinates and world
	  coordinates.
For languages other than C you should consult Part III, “ Supported computer languages ” for the details concerning how
	  PLTRANSFORM_callback arguments are interfaced.
	  However, in general, a particular pattern of
	  callback-associated arguments such as a tr vector
	  with 6 elements; xg and yg
	  vectors; or xg and yg matrices
	  are respectively interfaced to a linear-transformation routine similar
	  to the above mypltr function; pltr1; and pltr2.
	  Furthermore, some of our more sophisticated bindings (see, e.g., Chapter 10, Fortran Language) support native language callbacks for handling
	  index to world-coordinate transformations.  Examples of these various
	  approaches are given in
	  examples/<language>x09*,
	  examples/<language>x16*,
	  examples/<language>x20*,
	  examples/<language>x21*, and
	  examples/<language>x22*, for all our
	  supported languages.
pltr_data
	  (PLPointerExtra parameter to help pass information to pltr0, pltr1,
	  pltr2, or whatever callback routine that is externally
	  supplied.
Redacted form: plvect(u, v, scale, pltr,
    pltr_data) where (see above discussion) the pltr,
    pltr_data callback arguments are sometimes replaced by a
    tr vector with 6 elements, or xg
    and yg array arguments with either one or two
    dimensions.
This function is used in example 22.