added new hexplot image; added initial rough draft of FileInfo class for later refactoring

git-svn-id: https://svn.ssec.wisc.edu/repos/glance/trunk@128 8a9318a1-56ba-4d59-b755-99d26321be01

pyglance/glance/data.py

@@ -8,6 +8,7 @@ Copyright (c) 2010 University of Wisconsin SSEC. All rights reserved.
 """
 
 import logging
+import os, subprocess, datetime
 import numpy as np
 
 import glance.delta as delta
@@ -277,6 +278,78 @@ class DiffInfoObject (object) :
         
         return diff_data_object
 
+class FileInfo (object) :
+    """
+    This class represents information about a file object. It may or may not include the actual file object.
+    
+    The following member variables are available from this class:
+    
+    path          - the file path to reach the original file on disk
+    md5_sum       - an md5 sum calculated from the original file
+    last_modified - the time that the file was last modified (TODO, what form should this be in?)
+    file_object   - the file object that can be used to access the data in the file, may be None
+    """
+    
+    def __init__(self, pathToFile, md5sum=None, lastModifiedTime=None, fileObject=None) :
+        """
+        Create the file info object using the values given.
+        
+        If the md5 sum and last modified time aren't given, the initialization will figure them out.
+        Note: if the md5 sum is not given, the file object will also be loaded.
+        """
+        
+        self.path = pathToFile
+        
+        # if the file doesn't exist, stop
+        # TODO, is this the right strategy?
+        if not os.path.exists(self.path) :
+            LOG.warn("Requested file " + self.path + " could not be opened because it does not exist.")
+            self.md5_sum       = None
+            self.last_modified = None
+            self.file_object   = None
+            return
+        
+        # if the md5 sum isn't given, load the file and figure it out
+        if md5sum is None:
+            
+            # open the file
+            LOG.info("Opening " + self.path)
+            tempPath       = os.path.abspath(os.path.expanduser(self.path))
+            LOG.debug("Provided path after normalization and symbol expansion: " + tempPath)
+            fileObject     = io.open(tempPath, allowWrite=allowWrite)
+            
+            # figure out the md5 sum
+            tempSubProcess = subprocess.Popen("md5sum \'" + tempPath + "\'", shell=True, stdout=subprocess.PIPE)
+            md5sum         = tempSubProcess.communicate()[0].split()[0]
+            LOG.info("File md5sum: " + str(md5sum))
+            
+        self.md5_sum       = md5sum
+        self.file_object   = fileObject
+        
+        # if the last modified time isn't given, figure it out
+        if lastModifiedTime is None :
+            
+            statsForFile     = os.stat(os.path.abspath(os.path.expanduser(self.path)))
+            lastModifiedTime = datetime.datetime.fromtimestamp(statsForFile.st_mtime).ctime() # should time zone be forced?
+            LOG.info ("File was last modified: " + lastModifiedTime)
+            
+        self.last_modified = lastModifiedTime
+    
+    def get_version_without_file_object (self) :
+        """
+        get a version of this object without a file object
+        (this method is useful if you want file information but do not need access and want to save space)
+        """
+        toReturn = None
+        
+        if self.file_object is None:
+            toReturn = self
+        else:
+            toReturn = FileInfo(self.path, self.md5_sum, self.last_modified)
+        
+        return toReturn
+
+
 if __name__=='__main__':
     import doctest
     doctest.testmod()

pyglance/glance/figures.py

@@ -13,13 +13,14 @@ matplotlib.use('Agg') # use the Anti-Grain Geometry rendering engine
 
 from pylab import *
 
+import matplotlib.cm     as cm
 import matplotlib.pyplot as plt
 import matplotlib.colors as colors
-from matplotlib.ticker import FormatStrFormatter
+from   matplotlib.ticker import FormatStrFormatter
 
 import logging
 import numpy as np
-from numpy import ma 
+from   numpy import ma 
 
 import glance.graphics as maps
 import glance.delta    as delta
@@ -236,6 +237,34 @@ def create_scatter_plot(dataX, dataY, title, xLabel, yLabel, badMask=None, epsil
     
     return figure
 
+# build a hexbin plot of the x,y points and show the density of the point distribution
+def create_hexbin_plot(dataX, dataY, title, xLabel, yLabel) :
+    
+    # make the figure
+    figure = plt.figure()
+    axes = figure.add_subplot(111)
+    
+    # the hexbin plot of the good data 
+    plt.hexbin(dataX, dataY, bins='log', cmap=cm.jet)
+    plt.axis([dataX.min(), dataX.max(), dataY.min(), dataY.max()])
+    
+    # create a color bar
+    cb = plt.colorbar()
+    cb.set_label('log10 (count + 1)')
+    
+    # and some informational stuff
+    axes.set_title(title)
+    plt.xlabel(xLabel)
+    plt.ylabel(yLabel)
+    
+    # format our axes so they display gracefully
+    yFormatter = FormatStrFormatter("%4.4g")
+    axes.yaxis.set_major_formatter(yFormatter)
+    xFormatter = FormatStrFormatter("%4.4g")
+    axes.xaxis.set_major_formatter(xFormatter)
+    
+    return figure
+
 # build a histogram figure of the given data with the given title and number of bins
 def create_histogram(data, bins, title, xLabel, yLabel, displayStats=False) :
     

pyglance/glance/plotcreatefns.py

@@ -273,6 +273,18 @@ class BasicComparisonPlotsFunctionFactory (PlottingFunctionFactory) :
                                               "scatter plot of file a values vs file b values for " + variableDisplayName,
                                               "Scatter.png", compared_fig_list)
         
+        # make a hexplot, which is like a scatter plot with density
+        if ('do_plot_hex' not in doPlotSettingsDict) or (doPlotSettingsDict['do_plot_hex']) :
+            
+            assert(aData.shape == bData.shape)
+            assert(bData.shape == goodInBothMask.shape)
+            
+            functionsToReturn['scatterD']  = ((lambda : figures.create_hexbin_plot(aData[goodInBothMask], bData[goodInBothMask],
+                                                                                   "Value in File A vs Value in File B",
+                                                                                   "File A Value", "File B Value")),
+                                              "density of file a values vs file b values for " + variableDisplayName,
+                                              "Hex.png", compared_fig_list)
+        
         return functionsToReturn
 
 """