Download source and data
Histogram Legend Example
# Metview Macro
# **************************** LICENSE START ***********************************
#
# Copyright 2015 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 ************************************
# ------------------------------------------------------------------
# Tags: contour,legend
# Title: Positional and Histogram Legend
# Description: Demonstrates how to combine two fields into a single plot
# using contour and shade. A histogram legend is used for one
# of the fields.
# See also:
# https://software.ecmwf.int/magics/Legend+examples+legend3
# ------------------------------------------------------------------
# read the input grib files (temperature and geopotential)
my_data1 = read("./t850.grb")
my_data2 = read("./z500.grb")
# set up the geographical view
my_view = geoview(map_area_definition : "CORNERS",
map_projection : "POLAR_STEREOGRAPHIC",
area : [21.51,-37.27,51.28,65.00])
# set up a shade contour with legend for the temperature field
my_contour1 = mcont(contour_level_selection_type : "LEVEL_LIST",
contour_level_list : [-10.0,-8.0,-6.0,-4.0,-2.0,0.0,2.0,4.0,6.0,8.0,10.0],
contour : "OFF",
contour_label : "OFF",
contour_hilo : "OFF",
legend : "ON",
contour_shade : "ON",
contour_shade_method : "AREA_FILL",
contour_shade_colour_direction : "CLOCKWISE",
contour_shade_max_level_colour : "RED",
contour_shade_min_level_colour : "BLUE")
# set up a black contour line for the geopotential field
my_contour2 = mcont(contour_level_selection_type : "INTERVAL",
contour_line_colour : "BLACK",
contour_line_thickness : 1,
contour_hilo_height : 0.25,
contour_interval : 5.00,
contour_hilo : "ON",
contour_hilo_quality : "HIGH",
contour_highlight_colour : "BLACK",
contour_highlight_thickness : 2,
contour_label : "OFF",
legend : "OFF")
# set up the coastlines
my_coast= mcoast(map_coastline_resolution : "HIGH",
map_grid_colour : "CHARCOAL",
map_grid : "ON",
map_coastline_colour : "CHARCOAL")
# set up the title
my_title = mtext(text_font_size : 0.60,
text_lines : ["Positional and histogram legend","","","","","",""],
text_justification : "LEFT",
text_colour : "CHARCOAL")
# set up an histogram legend for the temperature field
my_legend = mlegend(legend_box_mode : "POSITIONAL",
legend_box_x_position : 1.00,
legend_box_x_length : 27.00,
legend_box_y_position : 16.00,
legend_box_y_length : 3.00,
legend_display_type : "HISTOGRAM",
legend_histogram_max_value : "ON",
legend_label_frequency : 1,
legend_text_font_size : 0.40,
legend_text_colour : "BLACK",
legend_title : "ON",
legend_title_text : "Temperature at 850 hPa")
# define the output plot file
setoutput(pdf_output(output_name : 'legend3'))
# plot the map
plot(my_view,my_data1,my_contour1,my_data2,my_contour2,my_coast,my_title,my_legend)
Histogram Legend Example
# Metview Example
# **************************** LICENSE START ***********************************
#
# Copyright 2015 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 ************************************
# ------------------------------------------------------------------
# Tags: contour,legend
# Title: Positional and Histogram Legend
# Description: Demonstrates how to combine two fields into a single plot
# using contour and shade. A histogram legend is used for one
# of the fields.
# See also:
# https://software.ecmwf.int/magics/Legend+examples+legend3
# ------------------------------------------------------------------
# read the input grib files (temperature and geopotential)
import metview as mv
my_data1 = mv.read("./t850.grb")
my_data2 = mv.read("./z500.grb")
# set up the geographical view
my_view = mv.geoview(map_area_definition = "CORNERS",
map_projection = "POLAR_STEREOGRAPHIC",
area = [21.51,-37.27,51.28,65.00])
# set up a shade contour with legend for the temperature field
my_contour1 = mv.mcont(contour_level_selection_type = "LEVEL_LIST",
contour_level_list = [-10.0,-8.0,-6.0,-4.0,-2.0,0.0,2.0,4.0,6.0,8.0,10.0],
contour = "OFF",
contour_label = "OFF",
contour_hilo = "OFF",
legend = "ON",
contour_shade = "ON",
contour_shade_method = "AREA_FILL",
contour_shade_colour_direction = "CLOCKWISE",
contour_shade_max_level_colour = "RED",
contour_shade_min_level_colour = "BLUE")
# set up a black contour line for the geopotential field
my_contour2 = mv.mcont(contour_level_selection_type = "INTERVAL",
contour_line_colour = "BLACK",
contour_line_thickness = 1,
contour_hilo_height = 0.25,
contour_interval = 5.00,
contour_hilo = "ON",
contour_hilo_quality = "HIGH",
contour_highlight_colour = "BLACK",
contour_highlight_thickness = 2,
contour_label = "OFF",
legend = "OFF")
# set up the coastlines
my_coast= mv.mcoast(map_coastline_resolution = "HIGH",
map_grid_colour = "CHARCOAL",
map_grid = "ON",
map_coastline_colour = "CHARCOAL")
# set up the title
my_title = mv.mtext(text_font_size = 0.60,
text_lines = ["Positional and histogram legend","","","","","",""],
text_justification = "LEFT",
text_colour = "CHARCOAL")
# set up an histogram legend for the temperature field
my_legend = mv.mlegend(legend_box_mode = "POSITIONAL",
legend_box_x_position = 1.00,
legend_box_x_length = 27.00,
legend_box_y_position = 16.00,
legend_box_y_length = 3.00,
legend_display_type = "HISTOGRAM",
legend_histogram_max_value = "ON",
legend_label_frequency = 1,
legend_text_font_size = 0.40,
legend_text_colour = "BLACK",
legend_title = "ON",
legend_title_text = "Temperature at 850 hPa")
# define the output plot file
mv.setoutput(mv.pdf_output(output_name = 'legend3'))
# plot the map
mv.plot(my_view,my_data1,my_contour1,my_data2,my_contour2,my_coast,my_title,my_legend)