def calculateCrosstable(self):
try:
self.rangeChanged.emit('Initialization...', 2)
self.updateProgress.emit()
self.crosstable = CrossTable(self.X, self.Y, expand=self.expand)
self.updateProgress.emit()
self.__propagateCrossTableSignals()
self.crosstable.computeCrosstable()
except MemoryError:
self.errorReport.emit(self.tr("The system out of memory during cross table calculation"))
raise
except:
self.errorReport.emit(self.tr("An unknown error occurs during cross table calculation"))
raise
finally:
self.processFinished.emit()
def __init__(self, initRaster, finalRaster):
QObject.__init__(self)
if not initRaster.geoDataMatch(finalRaster):
raise CrossTabManagerError('Geometries of the raster maps are different!')
if initRaster.getBandsCount() + finalRaster.getBandsCount() != 2:
raise CrossTabManagerError("An input raster has more then one band. Use 1-band rasters!")
self.pixelArea = initRaster.getPixelArea()
self.crosstable = CrossTable(initRaster.getBand(1), finalRaster.getBand(1))
self.crosstable.rangeChanged.connect(self.__crosstableProgressRangeChanged)
self.crosstable.updateProgress.connect(self.__crosstableProgressChanged)
self.crosstable.crossTableFinished.connect(self.__crosstableFinished)
self.crosstable.errorReport.connect(self.__crosstableError)
class DependenceCoef(QObject):
rangeChanged = pyqtSignal(str, int)
updateProgress = pyqtSignal()
processFinished = pyqtSignal()
logMessage = pyqtSignal(str)
errorReport = pyqtSignal(str)
def __init__(self, X, Y, expand=False):
"""
@param band1 First band (numpy masked array)
@param band2 Second band (numpy masked array)
@param expand If the param is True, use union of categories of the bands and compute NxN crosstable
"""
QObject.__init__(self)
self.X = X
self.Y = Y
self.expand = expand
self.crosstable = None
def getCrosstable(self):
if self.crosstable == None:
self.calculateCrosstable()
return self.crosstable
def calculateCrosstable(self):
try:
self.rangeChanged.emit('Initialization...', 2)
self.updateProgress.emit()
self.crosstable = CrossTable(self.X, self.Y, expand=self.expand)
self.updateProgress.emit()
self.__propagateCrossTableSignals()
self.crosstable.computeCrosstable()
except MemoryError:
self.errorReport.emit(self.tr("The system out of memory during cross table calculation"))
raise
except:
self.errorReport.emit(self.tr("An unknown error occurs during cross table calculation"))
raise
finally:
self.processFinished.emit()
def correlation(self):
'''
Define correlation coefficient of the rasters.
'''
x, y = masks_identity(self.X.flatten(), self.Y.flatten())
x, y = np.ma.compressed(x), np.ma.compressed(y)
R = np.corrcoef(x, y)
del x
del y
# function np.corrcoef returns array of coefficients
# R[0][0] = R[1][1] = 1.0 - correlation X--X and Y--Y
# R[0][1] = R[1][0] - correlation X--Y and Y--X
return R[0][1]
def correctness(self, percent = True):
"""
% (or count) of correct results
"""
table = self.getCrosstable()
crosstable = table.getCrosstable()
rows, cols = table.shape
if rows != cols:
raise CoeffError('The method is applicable for NxN crosstable only!')
n = table.n
s = 0.0
for i in range(rows):
s = s + crosstable[i][i]
if percent:
return 100.0*s/n
else:
return s/n
def cramer(self):
'''
Define Cramer's relationship coefficient of the rasters for discrete values
Coefficient change between [0, 1]
0 - no dependence
1 - full connection
@param X First raster's array
@param Y Second raster's array
'''
table = self.getCrosstable()
crosstable = table.getCrosstable()
rows, cols = table.shape
t_expect = table.getExpectedTable()
# Mask T* to prevent division by zero
t_expect = np.ma.array(t_expect, mask=(t_expect == 0))
# chi-square coeff = sum((T-T*)^2/T*)
x2 = np.sum(np.square(crosstable - t_expect)/t_expect)
# CRAMER CONTINGENCY COEF. = sqrt(chi-square / (total * min(s-1,r-1)))
# s, r - raster grauations
Cramer = math.sqrt(x2/(table.n*min(cols-1, rows-1)))
return Cramer
def jiu(self):
'''
Define Joint Information Uncertainty coef., based on entropy., for discrete values
Coefficient change between [0, 1]
0 - no connection
1 - full connection
@param X First raster's array
@param Y Second raster's array
'''
#T, sum_r, sum_s, total, r, s = compute_table(X, Y)
table = self.getCrosstable()
T = table.getProbtable() #Pij = Tij / total
sum_rows = table.getProbRows() #Pi. = Ti. / total i=[0,(r-1)]
sum_cols = table.getProbCols() #P.j = T.j / total j=[0,(s-1)]
#to calculate the entropy we take the logarithm,
#logarithm of zero does not exist, so we must mask zero values
sum_rows = np.compress(sum_rows != 0, sum_rows)
sum_cols = np.compress(sum_cols != 0, sum_cols)
#Compute the entropy coeff. of two raster
H_x = -np.sum(sum_rows * np.log(sum_rows))
H_y = -np.sum(sum_cols * np.log(sum_cols))
#Compute the joint entropy coeff.
T = np.ma.array(T, mask=(T == 0))
T = np.ma.compressed(T)
H_xy = -np.sum(T * np.log(T))
# Compute the Joint Information Uncertainty
U = 2.0 * ((H_x + H_y - H_xy)/(H_x + H_y))
return U
def kappa(self, mode=None):
'''
Kappa statistic
@param X Raster array.
@param Y Raster array.
@param mode Kappa sttistic to compute:
mode = None: classic kappa
mode = loc: kappa location
mode = histo kappa histogram
'''
table = self.getCrosstable()
rows, cols = table.shape
if rows != cols:
raise CoeffError('Kappa is applicable for NxN crosstable only!')
t_expect = table.getProbtable()
pa = 0
for i in range(rows):
pa = pa + t_expect[i,i]
prows = table.getProbRows()
pcols = table.getProbCols()
pexpect = sum(prows * pcols)
pmax = sum(np.min([prows, pcols], axis=0))
if mode == None:
result = (pa - pexpect)/(1-pexpect)
elif mode == "loc":
result = (pa - pexpect)/(pmax - pexpect)
elif mode == "histo":
result = (pmax - pexpect)/(1 - pexpect)
elif mode == "all":
result = {"loc": (pa - pexpect)/(pmax - pexpect), "histo": (pmax - pexpect)/(1 - pexpect), "overal": (pa - pexpect)/(1-pexpect)}
else:
raise CoeffError('Unknown mode of kappa statistics!')
return result
def __propagateCrossTableSignals(self):
self.crosstable.rangeChanged.connect(self.__crosstableProgressRangeChanged)
self.crosstable.updateProgress.connect(self.__crosstableProgressChanged)
self.crosstable.crossTableFinished.connect(self.__crosstableFinished)
self.crosstable.errorReport.connect(self.__crosstableError)
def __crosstableFinished(self):
self.crosstable.rangeChanged.disconnect(self.__crosstableProgressRangeChanged)
self.crosstable.updateProgress.disconnect(self.__crosstableProgressChanged)
self.crosstable.crossTableFinished.disconnect(self.__crosstableFinished)
def __crosstableProgressChanged(self):
QCoreApplication.processEvents()
self.updateProgress.emit()
def __crosstableProgressRangeChanged(self, message, maxValue):
self.rangeChanged.emit(message, maxValue)
def __crosstableError(self, message):
self.errorReport.emit(message)
class CrossTableManager(QObject):
'''
Provides statistic information about transitions InitState->FinalState.
'''
rangeChanged = pyqtSignal(str, int)
updateProgress = pyqtSignal()
crossTableFinished = pyqtSignal()
logMessage = pyqtSignal(str)
errorReport = pyqtSignal(str)
def __init__(self, initRaster, finalRaster):
QObject.__init__(self)
if not initRaster.geoDataMatch(finalRaster):
raise CrossTabManagerError('Geometries of the raster maps are different!')
if initRaster.getBandsCount() + finalRaster.getBandsCount() != 2:
raise CrossTabManagerError("An input raster has more then one band. Use 1-band rasters!")
self.pixelArea = initRaster.getPixelArea()
self.crosstable = CrossTable(initRaster.getBand(1), finalRaster.getBand(1))
self.crosstable.rangeChanged.connect(self.__crosstableProgressRangeChanged)
self.crosstable.updateProgress.connect(self.__crosstableProgressChanged)
self.crosstable.crossTableFinished.connect(self.__crosstableFinished)
self.crosstable.errorReport.connect(self.__crosstableError)
def __crosstableFinished(self):
self.crosstable.rangeChanged.disconnect(self.__crosstableProgressRangeChanged)
self.crosstable.updateProgress.disconnect(self.__crosstableProgressChanged)
self.crosstable.crossTableFinished.disconnect(self.__crosstableFinished)
self.crossTableFinished.emit()
def __crosstableProgressChanged(self):
self.updateProgress.emit()
def __crosstableProgressRangeChanged(self, message, maxValue):
self.rangeChanged.emit(message, maxValue)
def __crosstableError(self, message):
self.errorReport.emit(message)
def computeCrosstable(self):
try:
self.crosstable.computeCrosstable()
except MemoryError:
self.errorReport.emit(self.tr("The system out of memory during calculation of cross table"))
raise
except:
self.errorReport.emit(self.tr("An unknown error occurs during calculation of cross table"))
raise
def getCrosstable(self):
'''
dalam bentuk hectare
'''
return self.crosstable
def getTransitionMatrix(self):
'''
dalam bentuk proporsi
'''
tab = self.getCrosstable().getCrosstable()
s = 1.0/np.sum(tab, axis=1)
return tab*s[:,None]
def getTransitionStat(self):
pixelArea = self.pixelArea['area']
stat = {'unit': self.pixelArea['unit']}
tab = self.getCrosstable()
initArea = tab.getSumRows()
initArea = pixelArea * initArea
initPerc = 100.0 * initArea / sum(initArea)
stat['init'] = initArea
stat['initPerc'] = initPerc
finalArea = tab.getSumCols()
finalArea = pixelArea * finalArea
finalPerc = 100.0 * finalArea / sum(finalArea)
stat['final'] = finalArea
stat['finalPerc'] = finalPerc
deltas = finalArea - initArea
deltasPerc = finalPerc - initPerc
stat['deltas'] = deltas
stat['deltasPerc'] = deltasPerc
return stat
