#*****************************************************************************80
#
## volcano_surface makes a surface plot of height data near a volcano.
#
#  Licensing:
#
#    This code is distributed under the MIT license.
#
#  Modified:
#
#    30 August 2020
#
#  Author:
#
#    John Burkardt
#
cat ( "\n" )
cat ( "volcano_surface:\n" )
cat ( " ", version$version.string, "\n" )
cat ( "  Make a surface plot of volcano height.\n" )
#
#  Read the data.
#
filename = 'volcano_data.csv'
z <- read.csv ( file = filename, header = FALSE, sep = "," )
#
#  Convert data to a matrix.
#
z.matrix <- as.matrix ( z )

filename = 'volcano_surface.png'
png ( filename )

persp ( z.matrix,
  theta = 30,
  phi = 15,
  main = "surface plot of volcano height",
  xlab = "<-- X -->",
  ylab = "<-- Y -->",
  zlab = "<-- Z(X,Y) -->",
  col = "lightblue" )

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

quit ( )