Hovmoeller Area Average Example

# Metview Macro

#  **************************** LICENSE START ***********************************
# 
#  Copyright 2018 ECMWF. This software is distributed under the terms
#  of the Apache License version 2.0. In applying this license, ECMWF does not
#  waive the privileges and immunities granted to it by virtue of its status as
#  an Intergovernmental Organization or submit itself to any jurisdiction.
# 
#  ***************************** LICENSE END ************************************

# ----------------------------------------------------------------------
# Description: Demonstrates how to use a Hovmoeller View to
#              compute and plot an area average over time from GRIB data
# ----------------------------------------------------------------------


# read the GRIB data from file
t_ts = read("t_ts.grib")


# set up the view to plot the data into
# we will compute the average value along North/South lines over the
# given area. We also supply a custom Time Axis definition in order
# to increase the size of the date labels

time_axis = maxis(
    axis_type                : "date",
    axis_years_label_height  : 0.3,
    axis_months_label_height : 0.3,
    axis_days_label_height   : 0.3
)

hovmoeller_view = mhovmoellerview(
    type              : "area_hovm",
    area              : [53.4,-58.9,67.2,118.1],
    average_direction : "north_south",
    time_axis         : time_axis
    )

# set up the contouring style
shade = mcont(
    legend                      : "on",
    contour                     : "off",
    contour_level_count         : 8,
    contour_label               : "off",
    contour_shade               : "on",
    contour_shade_colour_method : "list",
    contour_shade_method        : "area_fill",
    contour_shade_colour_list   : ["blue", "sky", "blue_green", "grey", "cream",
                                   "yellowish_orange", "reddish_orange", "red"]
)


# set up the title, just to make the font bigger
title = mtext(
    text_font_size : 0.5
)


# define the output plot file
setoutput(pdf_output(output_name : 'hovmoeller_area'))

# plot the data into the Hovmoeller view with visdefs for styling
plot(hovmoeller_view, t_ts, shade, title)