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# Metview Example

# **************************** 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 ************************************

# ------------------------------------------------------------------
# Tags: ODB,Cartesian
# Title: ODB scatterplot with binning
# Description: Demonstrates how to generate a scatterpot from ODB 
#              using binning.
# ------------------------------------------------------------------

import metview as mv

use_mars = 0
if use_mars:
    #  retrieve from MARS - for AMSUA channel 5 (all satellites)
    db = mv.retrieve(
            type     = "mfb",
            repres   = "bu",
            obsgroup = "amsua",
            time     = 00,
            date     = -2,
            filter   = "select an_depar@body,fg_depar@body " +
                       "where vertco_reference_1=5"
            )
else:
    db = mv.read('amsua.odb')

# Define binning - with 100 bins both in the horizontal and vertical axes
bin_100 = mv.binning(
        binning_x_count := 100,
        binning_y_count := 100
        )

# Define visualiser for scatterplot with binning
bin_plot = mv.odb_visualiser(
        odb_plot_type      := "xy_binning",
        odb_x_variable     := "fg_depar@body",
        odb_y_variable     := "an_depar@body",
        odb_value_variable := "",
        #odb_where          := "vertco_reference_1@body =5 ",
        odb_data           := db,
        odb_binning        := bin_100
        )

# Define grid shading - the binned dataset will be defined on a grid
bin_grid_shade = mv.mcont(
        legend                         := "on",
        contour                        := "off",
        contour_min_level              := 1,
        contour_shade_min_level        := 1,
        contour_level_count            := 20,
        contour_shade                  := "on",
        contour_shade_technique        := "grid_shading",
        contour_shade_method           := "area_fill",
        contour_shade_max_level_colour := "red",
        contour_shade_min_level_colour := "blue",
        contour_shade_colour_direction := "clockwise"
        )

# Define title
title = mv.mtext(
        text_line_count := 1,
        text_line_1     := "Sensor: AMSU-A  Channel: 5 Param: Tb"
        )

# Define horizontal axis
hor_axis = mv.maxis(
        axis_position         := "left",
        axis_title_text       := "fg_depar (K)",
        axis_tick_interval    := 0.5,
        axis_minor_tick       := "on",
        axis_minor_tick_count := 4,
        axis_grid             := "on",
        axis_grid_colour      := "black",
        axis_grid_line_style  := "dot"
        )

# Define vertical axis 
ver_axis = mv.maxis(
        axis_orientation      := "vertical",
        axis_title_text       := "an_depar (K)",
        axis_tick_interval    := 0.5,
        axis_minor_tick       := "on",
        axis_minor_tick_count := 4,
        axis_grid             := "on",
        axis_grid_colour      := "black",
        axis_grid_line_style  := "dot"
        )

# Define Catresian view
scatter_view = mv.cartesianview(
        x_min              := -1,
        x_max              := 1,
        y_min              := -1,
        y_max              := 1,
        subpage_y_position := 12.5,
        subpage_y_length   := 75,
        horizontal_axis    := hor_axis,
        vertical_axis      := ver_axis
        )


# define the output plot file
mv.setoutput(mv.pdf_output(output_name := 'odb_scatterplot_binning'))

# Plot
mv.plot(scatter_view,bin_plot,bin_grid_shade,title)