コード例 #1
0
ファイル: PCAToolsTest.py プロジェクト: sjmvm/pymca
    def testPCAToolsPCA(self):
        from PyMca5.PyMcaMath.mva.PCATools import numpyPCA
        x = numpy.array([[0.0,  2.0,  3.0],
                         [3.0,  0.0, -1.0],
                         [4.0, -4.0,  4.0],
                         [4.0,  4.0,  4.0]])

        # that corresponds to 4 spectra of 3 channels
        nSpectra = x.shape[0]

        # calculate eigenvalues and eigenvectors with numpy
        tmpArray = numpy.dot(x.T, x)/(nSpectra - 1)
        numpyEigenvalues, numpyEigenvectors = numpy.linalg.eigh(tmpArray)

        # sort from higher to lower
        idx = list(range(numpyEigenvalues.shape[0]-1, -1 , -1))
        numpyEigenvalues = numpy.take(numpyEigenvalues, idx)
        numpyEigenvectors = numpyEigenvectors[:, ::-1].T

        # now use PyMca
        # centering has to be false to obtain the same results
        ncomp = x.shape[1]
        for force in [True, False]:
            images, eigenvalues, eigenvectors = numpyPCA(x,
                                                         ncomponents=ncomp,
                                                         force=force,
                                                         center=False,
                                                         scale=False)
            self.assertTrue(numpy.allclose(eigenvalues, numpyEigenvalues))
            for i in range(ncomp):
                if (eigenvectors[i,0] >= 0 and numpyEigenvectors[i,0] >=0) or\
                   (eigenvectors[i,0] <= 0 and numpyEigenvectors[i,0] <=0):
                    # both same sign
                    self.assertTrue(numpy.allclose(eigenvectors[i],
                                                   numpyEigenvectors[i]))
                else:
                    self.assertTrue(numpy.allclose(-eigenvectors[i],
                                                   numpyEigenvectors[i]))

        # test with a different shape
        x.shape = 2, 2, -1
        ncomp = 3
        for force in [True, False]:
            images, eigenvalues, eigenvectors = numpyPCA(x,
                                                         ncomponents=ncomp,
                                                         force=force,
                                                         center=False,
                                                         scale=False)
            self.assertTrue(numpy.allclose(eigenvalues, numpyEigenvalues))
            for i in range(ncomp):
                if (eigenvectors[i,0] >= 0 and numpyEigenvectors[i,0] >=0) or\
                   (eigenvectors[i,0] <= 0 and numpyEigenvectors[i,0] <=0):
                    # both same sign
                    self.assertTrue(numpy.allclose(eigenvectors[i],
                                                   numpyEigenvectors[i]))
                else:
                    self.assertTrue(numpy.allclose(-eigenvectors[i],
                                                   numpyEigenvectors[i]))
コード例 #2
0
ファイル: PCAToolsTest.py プロジェクト: sjmvm/pymca
        def testPCAToolsMDP(self):
            from PyMca5.PyMcaMath.mva.PCATools import getCovarianceMatrix, numpyPCA
            x = numpy.array([[0.0,  2.0,  3.0],
                             [3.0,  0.0, -1.0],
                             [4.0, -4.0,  4.0],
                             [4.0,  4.0,  4.0]])

            # use mdp
            pcaNode = mdp.nodes.PCANode()
            pcaNode.train(x)
            pcaNode.stop_training()
            pcaEigenvectors = pcaNode.v.T

            # and compare with PyMca
            ncomp = x.shape[1]
            for force in [True, False]:
                images, eigenvalues, eigenvectors = numpyPCA(x,
                                                        ncomponents=ncomp,
                                                        force=force,
                                                        center=True,
                                                        scale=False)

                # the eigenvalues must be the same
                self.assertTrue(numpy.allclose(eigenvalues, pcaNode.d))
                # the eigenvectors can be multiplied by -1
                for i in range(ncomp):
                    if (eigenvectors[i,0] >= 0 and pcaEigenvectors[i,0] >=0) or\
                       (eigenvectors[i,0] <= 0 and pcaEigenvectors[i,0] <=0):
                        # both same sign
                        self.assertTrue(numpy.allclose(eigenvectors[i],
                                                       pcaEigenvectors[i]))
                    else:
                        self.assertTrue(numpy.allclose(-eigenvectors[i],
                                                       pcaEigenvectors[i]))
コード例 #3
0
ファイル: PCAToolsTest.py プロジェクト: alemirone/pymca
        def testPCAToolsMDP(self):
            from PyMca5.PyMcaMath.mva.PCATools import getCovarianceMatrix, numpyPCA
            x = numpy.array([[0.0,  2.0,  3.0],
                             [3.0,  0.0, -1.0],
                             [4.0, -4.0,  4.0],
                             [4.0,  4.0,  4.0]])

            # use mdp
            pcaNode = mdp.nodes.PCANode()
            pcaNode.train(x)
            pcaNode.stop_training()
            pcaEigenvectors = pcaNode.v.T

            # and compare with PyMca
            for force in [True, False]:
                images, eigenvalues, eigenvectors = numpyPCA(x,
                                                        ncomponents=x.shape[1],
                                                        force=force,
                                                        center=True,
                                                        scale=False)

                # the eigenvalues must be the same
                self.assertTrue(numpy.allclose(eigenvalues, pcaNode.d))
                # the eigenvectors can be multiplied by -1
                for i in range(x.shape[1]):
                    if (eigenvectors[i,0] >= 0 and pcaEigenvectors[i,0] >=0) or\
                       (eigenvectors[i,0] <= 0 and pcaEigenvectors[i,0] <=0):
                        # both same sign
                        self.assertTrue(numpy.allclose(eigenvectors[i],
                                                       pcaEigenvectors[i]))
                    else:
                        self.assertTrue(numpy.allclose(-eigenvectors[i],
                                                       pcaEigenvectors[i]))
コード例 #4
0
ファイル: PCAToolsTest.py プロジェクト: alemirone/pymca
    def testPCAToolsPCA(self):
        from PyMca5.PyMcaMath.mva.PCATools import numpyPCA
        x = numpy.array([[0.0,  2.0,  3.0],
                         [3.0,  0.0, -1.0],
                         [4.0, -4.0,  4.0],
                         [4.0,  4.0,  4.0]])

        # that corresponds to 4 spectra of 3 channels
        nSpectra = x.shape[0]

        # calculate eigenvalues and eigenvectors with numpy
        tmpArray = numpy.dot(x.T, x)/(nSpectra - 1)
        numpyEigenvalues, numpyEigenvectors = numpy.linalg.eigh(tmpArray)

        # sort from higher to lower
        idx = list(range(numpyEigenvalues.shape[0]-1, -1 , -1))
        numpyEigenvalues = numpy.take(numpyEigenvalues, idx)
        numpyEigenvectors = numpyEigenvectors[:, ::-1].T

        # now use PyMca
        # centering has to be false to obtain the same results
        for force in [True, False]:
            images, eigenvalues, eigenvectors = numpyPCA(x,
                                                         ncomponents=x.shape[1],
                                                         force=force,
                                                         center=False,
                                                         scale=False)
            self.assertTrue(numpy.allclose(eigenvalues, numpyEigenvalues))
            self.assertTrue(numpy.allclose(eigenvectors, numpyEigenvectors))

        # test with a different shape
        x.shape = 2, 2, -1
        for force in [True, False]:
            images, eigenvalues, eigenvectors = numpyPCA(x,
                                                         ncomponents=3,
                                                         force=force,
                                                         center=False,
                                                         scale=False)
            self.assertTrue(numpy.allclose(eigenvalues, numpyEigenvalues))
            self.assertTrue(numpy.allclose(eigenvectors, numpyEigenvectors))