Python numpy.indices函数代码示例

def get_exmaple_regions(Page_Dist, Our_Docs, F,Per_Small, Per_Large0):
	Cut = 3 
	ind0 = np.round(np.random.uniform(0,len(F)))
	print(ind0)
	tA = F.tran_mat_index1.tolist()[int(ind0)]
	tB = F.tran_mat_index2.tolist()[int(ind0)]
	TFA = (Page_Dist[tA,:]<Per_Small) & (Page_Dist[tB,:]>Per_Large0)
	indexes=np.indices(Page_Dist.shape)
	indA = indexes[1,0,TFA]
	indApd=pd.DataFrame({'tran_mat_index':indA})
	indApd['Region'] = 'A'
	indApd['dist_to_A'] = Page_Dist[tA,indA] 
	indApd['dist_to_B'] = Page_Dist[tB,indA]
	indApd=indApd.sort_index(by = 'dist_to_A')
	indApd=indApd[0:Cut:1]
	TFB = (Page_Dist[tB,:]<Per_Small) & (Page_Dist[tA,:]>Per_Large0)
	indexes=np.indices(Page_Dist.shape)
	indB =indexes[1,0,TFB]
	indBpd=pd.DataFrame({'tran_mat_index':indB})
	indBpd['Region'] = 'B'
	indBpd['dist_to_A'] = Page_Dist[tA,indB] 
	indBpd['dist_to_B'] = Page_Dist[tB,indB]
	indBpd=indBpd.sort_index(by = 'dist_to_B')
	indBpd=indBpd[0:Cut:1]
	Info = pd.concat([indApd,indBpd])
	Info = join_replace(Info,Our_Docs[['usid_index','tran_mat_index','year','parties']],'tran_mat_index')
	MN = np.min(np.array([np.sum(TFA),np.sum(TFB)]))
	if MN<Cut: print("Too small")
	print(Info.to_string())
	return Info

	def __init__(self, Nm, Nf, L, qpf = 3):
		self.Nm = Nm
		self.Nf = Nf
		self.L = L
		self.qpf = qpf

		self.mass_res = L / Nm
		self.force_res = L / Nf

		self.X = np.indices((Nm, Nm)).astype(float)
		self.MX = self.X * self.mass_res

		# subdivide mass elements
		self.XX = (self.X.transpose([1,2,0]).reshape([Nm**2,2])[:,np.newaxis,:] + \
				subdiv_unitcell[self.qpf]).reshape([Nm**2 * 2**(2*self.qpf), 2])

		self.FX = np.indices((Nf, Nf)).astype(float) * self.force_res

		# k-values, divide by resolution to get physical scales
		self.Km = self.make_K(Nm)
		self.km2 = (self.Km**2).sum(axis=0)
		self.km2[0, 0] = 1

		self.Kf = self.make_K(Nf)
		self.kf2 = (self.Kf**2).sum(axis=0)
		self.kf2[0, 0] = 1

def shear_map(e1,e2,nx):
    
    n=e1.shape[0]
    field=numpy.zeros((nx,nx),dtype=double)
    x=double((numpy.indices([nx,nx])[0]))+0.5
    y=double((numpy.indices([nx,nx])[1]))+0.5

    fact=5.

    #matshow(field)
    eps=1.e-9
    
    etot=numpy.sqrt(e1**2+e2**2)
    
    phi=numpy.zeros((nx,nx),dtype=double)
    
    for l in xrange(nx):
        for k in xrange(nx):
            if (etot[l,k]>0):
                phi[l,k]=(math.acos(e1[l,k]/etot[l,k])*e2[l,k]/numpy.abs(e2[l,k]))/2.

    fct=5

    u=fct*etot*numpy.cos(phi)
    v=fct*etot*numpy.sin(phi)
    
    #u=1+numpy.zeros((nx,nx),dtype=double)
    #v=0.5+numpy.zeros((nx,nx),dtype=double)

    width=1
    Q=quiver(x,y,u,v,pivot='middle',units='width',headlength=0,headwidth=0,color='k')

def binary_mask_multiple(coords_rel, shape, radius, include_edge=True,
                         return_masks=False):
    """Creates multiple elliptical masks.

    Parameters
    ----------
    coords_rel : ndarray (N x 2 or N x 3)
        coordinates
    shape : tuple
        shape of the image
    radius : number or tuple of number
        size of the masks
    """
    ndim = len(shape)
    radius = validate_tuple(radius, ndim)
    coords_rel = np.atleast_2d(coords_rel)

    if include_edge:
        dist = [np.sum(((np.indices(shape).T - coord) / radius)**2, -1) <= 1
                for coord in coords_rel]
    else:
        dist = [np.sum(((np.indices(shape).T - coord) / radius)**2, -1) < 1
                for coord in coords_rel]
    mask_total = np.any(dist, axis=0).T
    masks_single = np.empty((len(coords_rel), mask_total.sum()), dtype=np.bool)
    if return_masks:
        for i, _dist in enumerate(dist):
            masks_single[i] = _dist.T[mask_total]
        return mask_total, masks_single
    else:
        return mask_total

def prepare_subimage(coords, image, radius, noise_size=None, threshold=None):
    ndim = image.ndim
    radius = validate_tuple(radius, ndim)
    # slice region around cluster
    im, origin = slice_image(coords, image, radius)
    if origin is None:   # coordinates are out of image bounds
        raise RefineException

    # do lowpass filter
    if noise_size is not None:
        if threshold is None:
            threshold = 0
        im = lowpass(im, noise_size, threshold)

    # include the edges where dist == 1 exactly
    dist = [(np.sum(((np.indices(im.shape).T - (coord - origin)) / radius)**2, -1) <= 1)
            for coord in coords]

    # to mask the image
    mask_total = np.any(dist, axis=0).T
    # to mask the masked image
    masks_singles = np.empty((len(coords), mask_total.sum()), dtype=np.bool)
    for i, _dist in enumerate(dist):
        masks_singles[i] = _dist.T[mask_total]

    # create the coordinates
    mesh = np.indices(im.shape, dtype=np.float64)[:, mask_total]
    # translate so that coordinates are in image coordinates
    mesh += np.array(origin)[:, np.newaxis]

    return im[mask_total].astype(np.float64), mesh, masks_singles

	def merge_transient(self, other_map):
		"""
		Like merge, but only makes a transient change
		"""
		assert isinstance(other_map, Map)
		assert self.resolution == other_map.resolution
		assert self.frame == other_map.frame
		assert self.orient == other_map.orient

		# Add the new map update to our map.

		# apply the local map
		mask = other_map.grid > 0
		i0, j0 = self.index_at(other_map.pos_at(0,0))
		i, j = np.indices(other_map.grid.shape)[:,mask]
		self.grid[i + i0,j + j0] += occupancy_weight # All occupied cells are now only slightly occupied

		# Check to see if we should make a laserscan diff
		if self.last_map_update:
			# Subtract the old laserscan data
			mask = self.last_map_update.grid > 0
			i0, j0 = self.index_at(self.last_map_update.pos_at(0,0))
			i, j = np.indices(self.last_map_update.grid.shape)[:,mask]
			self.grid[i + i0,j + j0] -= occupancy_weight # All occupied cells are now only slightly occupied

		# Save the old laserscan data
		self.last_map_update = other_map

    def coordinates(self, coord_type='skycoord', origin=0, mode='center'):
        """
        Sky coordinate images.

        Parameters
        ----------
        coord_type : {'pix', 'skycoord', 'galactic'}
            Which type of coordinates to return.
        origin : {0, 1}
            Pixel coordinate origin.
        mode : {'center', 'edges'}
            Return coordinate values at the pixels edges or pixel centers.
        """
        if mode == 'center':
            y, x = np.indices(self.data.shape)
        elif mode == 'edges':
            shape = self.data.shape[0] + 1, self.data.shape[1] + 1
            y, x = np.indices(shape)
            y, x = y - 0.5, x - 0.5
        else:
            raise ValueError('Invalid mode to compute coordinates.')

        if coord_type == 'pix':
            return x, y
        else:
            coordinates = pixel_to_skycoord(x, y, self.wcs, origin)
            if coord_type == 'skycoord':
                return coordinates
            elif coord_type == 'galactic':
                l = coordinates.galactic.l.wrap_at('180d')
                b = coordinates.galactic.b
                return l, b
            else:
                raise ValueError("Not a valid coordinate type. Choose either"
                                 " 'pix' or 'skycoord'.")

def simpleCentroid(img, threshold_frac=0, **kwargs):
    '''
    Centroids an image, or an array of images.
    Centroids over the last 2 dimensions.
    Sets all values under "threshold_frac*max_value" to zero before centroiding
    '''
    if threshold_frac!=0:
        if len(img.shape)==2:
            img = numpy.where(img>threshold_frac*img.max(), img, 0 )
        else:
            img_temp = (img.T - threshold_frac*img.max(-1).max(-1)).T
            zero_coords = numpy.where(img_temp<0)
            img[zero_coords] = 0

    if len(img.shape)==2:
        y_cent,x_cent = numpy.indices(img.shape)
        y_centroid = (y_cent*img).sum()/img.sum()
        x_centroid = (x_cent*img).sum()/img.sum()

    else:
        y_cent, x_cent = numpy.indices((img.shape[-2],img.shape[-1]))
        y_centroid = (y_cent*img).sum(-1).sum(-1)/img.sum(-1).sum(-1)
        x_centroid = (x_cent*img).sum(-1).sum(-1)/img.sum(-1).sum(-1)

    y_centroid+=0.5
    x_centroid+=0.5

    return numpy.array([y_centroid,x_centroid])

def generate_result_maps(data, sourcelist):
    """Return a source and residual image

    Given a data array (image) and list of sources, return two images, one
    showing the sources themselves and the other the residual after the
    sources have been removed from the input data.
    """
    residual_map = numpy.array(data) # array constructor copies by default
    gaussian_map = numpy.zeros(residual_map.shape)
    for src in sourcelist:
        # Include everything with 6 times the std deviation along the major
        # axis. Should be very very close to 100% of the flux.
        box_size = 6 * src.smaj.value / math.sqrt(2 * math.log(2))

        lower_bound_x = max(0, int(src.x.value - 1 - box_size))
        upper_bound_x = min(residual_map.shape[0], int(src.x.value - 1 + box_size))
        lower_bound_y = max(0, int(src.y.value - 1 - box_size))
        upper_bound_y = min(residual_map.shape[1], int(src.y.value - 1 + box_size))

        local_gaussian = gaussian(
            src.peak.value,
            src.x.value,
            src.y.value,
            src.smaj.value,
            src.smin.value,
            src.theta.value
        )(
            numpy.indices(residual_map.shape)[0,lower_bound_x:upper_bound_x,lower_bound_y:upper_bound_y],
            numpy.indices(residual_map.shape)[1,lower_bound_x:upper_bound_x,lower_bound_y:upper_bound_y]
        )

        gaussian_map[lower_bound_x:upper_bound_x, lower_bound_y:upper_bound_y] += local_gaussian
        residual_map[lower_bound_x:upper_bound_x, lower_bound_y:upper_bound_y] -= local_gaussian

    return gaussian_map, residual_map

def test_psi_continuous():
    # first make perfect prediction, including pairwise part
    X, Y = toy.generate_blocks_multinomial(noise=2, n_samples=1, seed=1)
    x, y = X[0], Y[0]
    n_states = x.shape[-1]

    pw_horz = -1 * np.eye(n_states)
    xx, yy = np.indices(pw_horz.shape)
    # linear ordering constraint horizontally
    pw_horz[xx > yy] = 1

    # high cost for unequal labels vertically
    pw_vert = -1 * np.eye(n_states)
    pw_vert[xx != yy] = 1
    pw_vert *= 10

    # create crf, assemble weight, make prediction
    crf = DirectionalGridCRF(n_states=3, inference_method='lp')
    w = np.hstack([np.ones(3), -pw_horz.ravel(), -pw_vert.ravel()])
    y_pred = crf.inference(x, w, relaxed=True)

    # compute psi for prediction
    psi_y = crf.psi(x, y_pred)
    assert_equal(psi_y.shape, (crf.size_psi,))
    # first unary, then horizontal, then vertical
    unary_psi = crf.get_unary_weights(psi_y)
    pw_psi_horz, pw_psi_vert = crf.get_pairwise_weights(psi_y)

    # test unary
    xx, yy = np.indices(y.shape)
    assert_array_almost_equal(unary_psi,
                              np.bincount(y.ravel(), x[xx, yy, y].ravel()))

def centreOfGravity(img, threshold=0, **kwargs):
    '''
    Centroids an image, or an array of images.
    Centroids over the last 2 dimensions.
    Sets all values under "threshold*max_value" to zero before centroiding
    Origin at 0,0 index of img.

    Parameters:
        img (ndarray): ([n, ]y, x) 2d or greater rank array of imgs to centroid
        threshold (float): Percentage of max value under which pixels set to 0

    Returns:
        ndarray: Array of centroid values (2[, n])

    '''
    if threshold!=0:
        if len(img.shape)==2:
            img = numpy.where(img>threshold*img.max(), img, 0 )
        else:
            img_temp = (img.T - threshold*img.max(-1).max(-1)).T
            zero_coords = numpy.where(img_temp<0)
            img[zero_coords] = 0

    if len(img.shape)==2:
        y_cent,x_cent = numpy.indices(img.shape)
        y_centroid = (y_cent*img).sum()/img.sum()
        x_centroid = (x_cent*img).sum()/img.sum()

    else:
        y_cent, x_cent = numpy.indices((img.shape[-2],img.shape[-1]))
        y_centroid = (y_cent*img).sum(-1).sum(-1)/img.sum(-1).sum(-1)
        x_centroid = (x_cent*img).sum(-1).sum(-1)/img.sum(-1).sum(-1)

    return numpy.array([x_centroid, y_centroid])

 def prep_image(self):
   """Takes the solved coordinate system and makes a piecewise \
   transform on the origin image to the target image"""
   transform = ProjectiveTransform()
   self.coord_solver.coordinates = self.coord_solver.min_coords.copy()
   self.new_image = np.zeros(self.coord_solver.image.shape)
   coords = np.array([self.coord_solver.coordinates[x:x+2, y:y+2, :].reshape([4, 2]) for x in \
     range(self.coord_solver.coordinates.shape[0]) for y in range(self.coord_solver.coordinates.shape[1]) \
     if (self.coord_solver.coordinates[x:x+2, y:y+2, :].shape == (2, 2, 2))])
   canonical_coords = np.indices((self.coord_solver.width, self.coord_solver.height)).T.astype('float32')
   flattened_canonical = np.array([canonical_coords[x:x+2, y:y+2, :].reshape([4, 2]) for x in \
     range(canonical_coords.shape[0]-1) for y in range(canonical_coords.shape[1]-1)])
   mesh_size = self.coord_solver.mesh_factor
   print "needs %s calcs" % coords.shape[0]
   coord_grid = np.indices(self.coord_solver.image.shape[:-1]).T.astype('float32').reshape(-1,2)
   for k in range(coords.shape[0]):
     des = mesh_size*coords[k, :, :]
     canon_coord = mesh_size*flattened_canonical[k, :, :]
     src = mesh_size*flattened_canonical[0, :, :]
     if not transform.estimate(des, canon_coord):
       raise Exception("estimate failed at %s" % str(k))
     area_in_question_x = canon_coord[0, 0].astype(int)
     area_in_question_y = canon_coord[0, 1].astype(int)
     scaled_area = tf.warp(self.coord_solver.image, transform)
     area_path = path.Path([des[0],des[1],des[3],des[2],des[0]])
     points_in_area = area_path.contains_points(coord_grid,radius=0.00001).reshape(self.coord_solver.image.shape[:-1])
     self.new_image += scaled_area*points_in_area[:,:,np.newaxis]

def find_mode(ndarray,axis=0):
    if ndarray.size == 1:
        return (ndarray[0],1)
    elif ndarray.size == 0:
        raise Exception('Attempted to find mode on an empty array!')
    try:
        axis = [i for i in range(ndarray.ndim)][axis]
    except IndexError:
        raise Exception('Axis %i out of range for array with %i dimension(s)' % (axis,ndarray.ndim))

    srt = numpy.sort(ndarray,axis=axis)
    dif = numpy.diff(srt,axis=axis)
    shape = [i for i in dif.shape]
    shape[axis] += 2
    indices = numpy.indices(shape)[axis]
    index = tuple([slice(None) if i != axis else slice(1,-1) for i in range(dif.ndim)])
    indices[index][dif == 0] = 0
    indices.sort(axis=axis)
    bins = numpy.diff(indices,axis=axis)
    location = numpy.argmax(bins,axis=axis)
    mesh = numpy.indices(bins.shape)
    index = tuple([slice(None) if i != axis else 0 for i in range(dif.ndim)])
    index = [mesh[i][index].ravel() if i != axis else location.ravel() for i in range(bins.ndim)]
    #counts = bins[tuple(index)].reshape(location.shape)
    index[axis] = indices[tuple(index)]
    modals = srt[tuple(index)].reshape(location.shape)
    mode = modals[()]
    return (mode)

    def vmax_discretized(self, Value, s, xij, i, j):

        nx = self.dims.nx
        ns = s.shape[-1]
        dx = self.dims.dx
        X = self.options.X

        vv = np.full((nx, ns), -np.inf)

        xl, xu = self.bounds(s, i, j)
        xl = xl.T
        xu = xu.T

        for h, x0 in enumerate(X.T):
            is_= np.all((xl <= x0) & (x0 <= xu), 1)
            if np.any(is_):
                xx = np.repeat(x0, ns, 0)
                vv[h, is_] = self.__Bellman_rhs_discrete(Value, xx, s, i, j)

        xmax = np.argmax(vv, 0)

        vxs = [a[0] for a in np.indices(vv.shape)]  # the [0] reduces one dimension
        vxs[0] = xmax
        vij = vv[vxs]

        xxs = [a[0] for a in np.indices(X.T.shape)]
        xxs[0] = xmax
        xij[:] = X.T[xxs]

        return vij

 def __init__(self, image=None, mesh_factor=14, density_distribution=None):
   super(CoordinateSolver, self).__init__()
   self.image = image
   self.height, self.width, _ = self.image.shape
   self.mesh_factor = mesh_factor
   self.height /= self.mesh_factor
   self.width /= self.mesh_factor
   self.image = self.image[:self.mesh_factor*self.height, :self.mesh_factor*self.width]
   if type(density_distribution) == np.ndarray:
     restricted_density = density_distribution[:self.mesh_factor*self.height, :self.mesh_factor*self.width]
     target_areas = restricted_density
     target_areas = target_areas[:-1, :-1]
   else:
     target_areas = np.indices((self.width-1, self.height-1)).T.astype('float32')
     target_areas = norm.pdf(target_areas[:, :, 0], self.width/2, self.width/5)\
                   *norm.pdf(target_areas[:, :, 1], self.height/2, self.height/5)
   target_areas /= sum(sum(target_areas))
   
   normalisation_factor = (self.height-1)*(self.width-1)
   target_areas_normalised = target_areas*normalisation_factor
   self.padded_targets = np.zeros([self.height+1, self.width+1])
   self.padded_targets[1:-1, 1:-1] = target_areas_normalised
   self.coordinates = np.indices((self.width, self.height)).T.astype('float32')
   self.total_error = (self.height-1)*(self.width-1)
   
   self.min_coords = self.coordinates.copy()
   self.areas = calculate_areas(self.coordinates)
   self.errors = np.zeros(self.padded_targets.shape)
   self.x_weights = np.ones([self.height*self.width, self.height + 1, self.width + 1])
   self.y_weights = np.ones([self.height*self.width, self.height + 1, self.width + 1])
   self.make_weights()