#*****************************************************************************80
#
## temperature_scatter3d creates a 3D scatter plot of temperature reading stations.
#
#  Discussion:
#
#    This function requires the scatterplot3d library.  To install it, start R
#    and type:
#
#      install.packages ( "scatterplot3d" )
#
#  Licensing:
#
#    This code is distributed under the MIT license. 
#
#  Modified:
#
#    31 August 2020
#
#  Author:
#
#    John Burkardt
#
library ( scatterplot3d )

cat ( date ( ), "\n" )
cat ( "\n" )
cat ( "temperature_scatter3d\n" )
cat ( " ", version$version.string, "\n" )
cat ( "  Create a 3D scatter plot of longitude\n" )
cat ( "  latitude, and January temperature.\n" );

filename = "temperature_data.txt"
tll <- read.table ( filename, header = FALSE )

filename = "temperature_scatter3d.png"

png ( filename )
scatterplot3d ( tll[,1], tll[,2], tll[,3], 
  xlab = "<-- Longitude -->", 
  ylab = "<-- Latitude -->",
  zlab = "<-- January temperature -->",
  main = "Location of January Temperature Readings" )
grid ( )

cat ( '  Graphics saved as "', filename, '"\n' )
#
#  Terminate.
#
cat ( "\n" )
cat ( "temperature_scatter3d:\n" )
cat ( "  Normal end of execution.\n" )

quit ( )