#*****************************************************************************80
#
## brownian_2d_plot plots Brownian motion in 2D.
#
#  Licensing:
#
#    This code is distributed under the MIT license.
#
#  Modified:
#
#    21 August 2020
#
#  Author:
#
#    John Burkardt
#
cat ( "\n" );
cat ( "brownian_2d_plot:\n" );
cat ( " ", version$version.string, "\n" )
cat ( "  Plot Brownian motion in two dimensions.\n" );

filename = "brownian_2d_data.txt"
xy <- read.table ( filename, header = FALSE )

n = dim ( xy )[1]
#
#  Plot the data.
#
filename = "brownian_2d_plot.png"
png ( filename )

plot ( xy[,1], xy[,2],
  xlab = "<--- X --->",
  ylab = "<--- Y --->",
  main = "Brownian motion in two dimensions",
  col = "blue",
  type = 'l' )
lines ( xy[1,1], xy[1,2], type = 'p', lwd = 20, col = "green" )
lines ( xy[n,1], xy[n,2], type = 'p', lwd = 20, col = "red" )

grid ( )

cat ( "\n" )
cat ( '  Graphics saved as "', filename, '"\n' )
#
#  Terminate.
#
cat ( "\n" )
cat ( "brownian_2d_plot\n" )
cat ( "  Normal end of execution.\n" )
quit ( )