Routines (alphabetical) > Routines: A > ARROW Procedure

# ARROW Procedure

The ARROW procedure draws one or more vectors with arrow heads.

This routine is written in the IDL language. Its source code can be found in the file `arrow.pro` in the `lib` subdirectory of the IDL distribution.

## Examples

Draw an arrow from (100,150) to (300,350) in DEVICE units:

ARROW, 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)
PLOT, X, Y
ARROW, X, REPLICATE(0,50), X, Y, /DATA

## Syntax

ARROW, X0, Y0, X1, Y1 [, /DATA | , /NORMALIZED] [, HSIZE=length] [, COLOR=index] [, HTHICK=value] [, /SOLID] [, THICK=value]

## Arguments

### X0, Y0

Arrays or scalars containing the coordinates of the tail end of the vector or vectors. Coordinates are in DEVICE coordinates unless otherwise specified.

### X1,Y1

Arrays or scalars containing the coordinates of the arrowhead end of the vector or vectors. X1 and Y1 must have the save number of elements as X0 and Y0.

## Keywords

### DATA

Set this keyword if vector coordinates are DATA coordinates.

### NORMALIZED

Set this keyword if vector coordinates are NORMALIZED coordinates.

### HSIZE

Use this keyword to set the length of the lines used to draw the arrowhead. The default is 1/64th the width of the display (!D.X_SIZE / 64.). If the HSIZE is positive, the value is assumed to be in device coordinate units. If HSIZE is negative, the arrowhead length is set to the vector length * ABS(HSIZE). The lines are separated by 60 degrees to make the arrowhead.

### COLOR

The color of the arrow. The default is the highest color index.

### HTHICK

The thickness of the arrowheads. The default is 1.0.

### SOLID

Set this keyword to make a solid arrow, using polygon fills, looks better for thick arrows.

### THICK

The thickness of the body. The default is 1.0.

## Version History

Pre 4.0 | Introduced

## See Also

ANNOTATE Procedure, PLOTS Procedure, VELOVECT Procedure