Name

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    CAT_IDLARROW
  PURPOSE: Draw a vector(s) with an arrow head
  CATEGORY: Graphics

Calling Sequence

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  CAT_IDLARROW, x0, y0, x1, y1

Inputs

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  (x0, y0) = coordinates of beginning of vector(s). May be arrays
  or scalars. Coordinates are in DEVICE coordinates
  unless otherwise specified.
  (x1, y1) = coordinates of endpoint (head) of vector.
  x0, y0, x1, y1 must all have the same number of elements.

Keyword Parameters

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  DATA - if set, implies that coordinates are in data coords.
  NORMALIZED - if set, coordinates are specified in normalized coords.
  HSIZE = size of arrowhead. Default = 1/64th the width of the device,
  (!D.X_SIZE / 64.).
  If the size is positive, it is assumed to be in device
  coordinate units. If it is NEGATIVE, then the head length
  is set to the vector length * abs(hsize), giving heads
  proportional in size to the bodies. The size is defined as
  the length of each of the lines (separated by 60 degrees)
  that make the head.
  COLOR = drawing color. Default = highest color index.
  HTHICK = thickness of heads. Default = 1.0.
  SOLID = if set, make a solid arrow, using polygon fills, looks better
  for thick arrows.
  THICK = thickness of body. Default = 1.0.

Outputs

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  No explicit outputs.

Side Effects

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Restrictions

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Procedure

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  Straightforward.

Examples

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      Draw an arrow from (100,150) to (300,350) in DEVICE units.
  CAT_IDLARROW, 100, 150, 300, 350
  Draw a sine wave with arrows from the line Y=0 to
  sin(x/4).
  X = FINDGEN(50)
  Y = SIN(x/4) ;Make sin wave
  PLOT, X, Y
  CAT_IDLARROW, X, REPLICATE(0,50), X, Y, /DATA

Modification History

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  DMS, Feb, 1992.
  DMS, Sept, 1992. Added /SOLID.
  Renamed program CAT_IDLARROW and added LINESTYLE and _EXTRA keywords. Changed default
    arrowhead size to 1/32nd of width of the device. DWF