20080222a.py

"""
Visualize a matrix as a heat map.
"""

import numpy as np

from SnippetUtil import HandlingError
import SnippetUtil
import EnglishModel
import HeatMap
import MatrixUtil
import Form
import FormOut

def get_form():
    """
    @return: the body of a form
    """
    # define the default matrix lines
    dictionary_rate_matrix = EnglishModel.get_transition_matrix()
    labels = list(sorted(set(a for a, b in dictionary_rate_matrix)))
    T = MatrixUtil.dict_to_row_major(dictionary_rate_matrix, labels, labels)
    T = np.array(T)
    # define the form objects
    form_objects = [
            Form.Matrix('matrix', 'matrix', T),
            Form.Integer('maxcategories', 'maximum number of categories',
                5, low=2)]
    return form_objects

def get_form_out():
    return FormOut.Html()

def get_response_content(fs):
    """
    @param fs: a FieldStorage object containing the cgi arguments
    @return: a (response_headers, response_text) pair
    """
    # create the html response representing the heat map
    M = fs.matrix
    heatmap = HeatMap.HeatMap(M.tolist(), fs.maxcategories)
    renderer = HeatMap.PreHeatMap(heatmap)
    html_string = renderer.get_example_html()
    # return the response
    return html_string + '\n'