Python numpy.multiply() Examples

def image(self, captcha_str):
        """
        Generate a greyscale captcha image representing number string

        Parameters
        ----------
        captcha_str: str
            string a characters for captcha image

        Returns
        -------
        numpy.ndarray
            Generated greyscale image in np.ndarray float type with values normalized to [0, 1]
        """
        img = self.captcha.generate(captcha_str)
        img = np.fromstring(img.getvalue(), dtype='uint8')
        img = cv2.imdecode(img, cv2.IMREAD_GRAYSCALE)
        img = cv2.resize(img, (self.h, self.w))
        img = img.transpose(1, 0)
        img = np.multiply(img, 1 / 255.0)
        return img 

def get_audio_data(self):
        frames = self.rec.get_frames()
        result = [0] * self.bins
        if len(frames) > 0:
            # keeps only the last frame
            current_frame = frames[-1]
            # plots the time signal
            # self.line_top.set_data(self.time_vect, current_frame)
            # computes and plots the fft signal
            fft_frame = np.fft.rfft(current_frame)
            if self.auto_gain:
                fft_frame /= np.abs(fft_frame).max()
            else:
                fft_frame *= (1 + self.gain) / 5000000.

            fft_frame = np.abs(fft_frame)
            if self.log_scale:
                fft_frame = np.log10(np.add(1, np.multiply(10, fft_frame)))

            result = [min(int(max(i, 0.) * 1023), 1023) for i in fft_frame][0:self.bins]

        return result 

def get_audio_data(self):
        frames = self.rec.get_frames()
        result = [0] * self.bins
        if len(frames) > 0:
            # keeps only the last frame
            current_frame = frames[-1]
            # plots the time signal
            # self.line_top.set_data(self.time_vect, current_frame)
            # computes and plots the fft signal
            fft_frame = np.fft.rfft(current_frame)
            if self.auto_gain:
                fft_frame /= np.abs(fft_frame).max()
            else:
                fft_frame *= (1 + self.gain) / 5000000.

            fft_frame = np.abs(fft_frame)
            if self.log_scale:
                fft_frame = np.log10(np.add(1, np.multiply(10, fft_frame)))

            result = [min(int(max(i, 0.) * 1023), 1023) for i in fft_frame][0:self.bins]

        return result 

def cost0(params, input_size, hidden_size, num_labels, X, y, learning_rate):
    m = X.shape[0]
    X = np.matrix(X)
    y = np.matrix(y)
    
    # reshape the parameter array into parameter matrices for each layer
    theta1 = np.matrix(np.reshape(params[:hidden_size * (input_size + 1)], (hidden_size, (input_size + 1))))
    theta2 = np.matrix(np.reshape(params[hidden_size * (input_size + 1):], (num_labels, (hidden_size + 1))))
    
    # run the feed-forward pass
    a1, z2, a2, z3, h = forward_propagate(X, theta1, theta2)
    
    # compute the cost
    J = 0
    for i in range(m):
        first_term = np.multiply(-y[i,:], np.log(h[i,:]))
        second_term = np.multiply((1 - y[i,:]), np.log(1 - h[i,:]))
        J += np.sum(first_term - second_term)
    
    J = J / m
    
    return J 

def cost(params, input_size, hidden_size, num_labels, X, y, learning_rate):
    m = X.shape[0]
    X = np.matrix(X)
    y = np.matrix(y)
    
    # reshape the parameter array into parameter matrices for each layer
    theta1 = np.matrix(np.reshape(params[:hidden_size * (input_size + 1)], (hidden_size, (input_size + 1))))
    theta2 = np.matrix(np.reshape(params[hidden_size * (input_size + 1):], (num_labels, (hidden_size + 1))))
    
    # run the feed-forward pass
    a1, z2, a2, z3, h = forward_propagate(X, theta1, theta2)
    
    # compute the cost
    J = 0
    for i in range(m):
        first_term = np.multiply(-y[i,:], np.log(h[i,:]))
        second_term = np.multiply((1 - y[i,:]), np.log(1 - h[i,:]))
        J += np.sum(first_term - second_term)
    
    J = J / m
    
    # add the cost regularization term
    J += (float(learning_rate) / (2 * m)) * (np.sum(np.power(theta1[:,1:], 2)) + np.sum(np.power(theta2[:,1:], 2)))
    
    return J 

def cost(params, Y, R, num_features):
    Y = np.matrix(Y)  # (1682, 943)
    R = np.matrix(R)  # (1682, 943)
    num_movies = Y.shape[0]
    num_users = Y.shape[1]
    
    # reshape the parameter array into parameter matrices
    X = np.matrix(np.reshape(params[:num_movies * num_features], (num_movies, num_features)))  # (1682, 10)
    Theta = np.matrix(np.reshape(params[num_movies * num_features:], (num_users, num_features)))  # (943, 10)
    
    # initializations
    J = 0
    
    # compute the cost
    error = np.multiply((X * Theta.T) - Y, R)  # (1682, 943)
    squared_error = np.power(error, 2)  # (1682, 943)
    J = (1. / 2) * np.sum(squared_error)
    
    return J 

def gradientReg(theta, X, y, learningRate):
    theta = np.matrix(theta)
    X = np.matrix(X)
    y = np.matrix(y)
    
    parameters = int(theta.ravel().shape[1])
    grad = np.zeros(parameters)
    
    error = sigmoid(X * theta.T) - y
    
    for i in range(parameters):
        term = np.multiply(error, X[:,i])
        
        if (i == 0):
            grad[i] = np.sum(term) / len(X)
        else:
            grad[i] = (np.sum(term) / len(X)) + ((learningRate / len(X)) * theta[:,i])
    
    return grad 

def forward_ocr(self, img_):
        img_ = cv2.resize(img_, (80, 30))
        img_ = img_.transpose(1, 0)
        print(img_.shape)
        img_ = img_.reshape((1, 80, 30))
        print(img_.shape)
        # img_ = img_.reshape((80 * 30))
        img_ = np.multiply(img_, 1 / 255.0)
        self.predictor.forward(data=img_, **self.init_state_dict)
        prob = self.predictor.get_output(0)
        label_list = []
        for p in prob:
            print(np.argsort(p))
            max_index = np.argsort(p)[::-1][0]
            label_list.append(max_index)
        return self.__get_string(label_list) 

def get_cosine_dist(A, B):
    B = np.reshape(B, (1, -1))
    
    if A.shape[1] == 1:
        A = np.hstack((A, np.zeros((A.shape[0], 1))))
        B = np.hstack((B, np.zeros((B.shape[0], 1))))
    
    aa = np.sum(np.multiply(A, A), axis=1).reshape(-1, 1)
    bb = np.sum(np.multiply(B, B), axis=1).reshape(-1, 1)
    ab = A @ B.T
    
    # to avoid NaN for zero norm
    aa[aa==0] = 1
    bb[bb==0] = 1
    
    D = np.real(np.ones((A.shape[0], B.shape[0])) - np.multiply((1/np.sqrt(np.kron(aa, bb.T))), ab))
    
    return D 

def calWeights(self, img, kernel, y, x):
        wmax = 0
        sweight = 0
        average = 0
        for j in range(2 * self.Ds + 1 - 2 * self.ds - 1):
            for i in range(2 * self.Ds + 1 - 2 * self.ds - 1):
                start_y = y - self.Ds + self.ds + j
                start_x = x - self.Ds + self.ds + i
                neighbour_w = img[start_y - self.ds:start_y + self.ds + 1, start_x - self.ds:start_x + self.ds + 1]
                center_w = img[y-self.ds:y+self.ds+1, x-self.ds:x+self.ds+1]
                if j != y or i != x:
                    sub = np.subtract(neighbour_w, center_w)
                    dist = np.sum(np.multiply(kernel, np.multiply(sub, sub)))
                    w = np.exp(-dist/pow(self.h, 2))    # replaced by look up table
                    if w > wmax:
                        wmax = w
                    sweight = sweight + w
                    average = average + w * img[start_y, start_x]
        return sweight, average, wmax 

def execute(self):
        img_pad = self.padding()
        img_pad = img_pad.astype(np.uint16)
        raw_h = self.img.shape[0]
        raw_w = self.img.shape[1]
        bnf_img = np.empty((raw_h, raw_w), np.uint16)
        rdiff = np.zeros((5,5), dtype='uint16')
        for y in range(img_pad.shape[0] - 4):
            for x in range(img_pad.shape[1] - 4):
                for i in range(5):
                    for j in range(5):
                        rdiff[i,j] = abs(img_pad[y+i,x+j] - img_pad[y+2, x+2])
                        if rdiff[i,j] >= self.rthres[0]:
                            rdiff[i,j] = self.rw[0]
                        elif rdiff[i,j] < self.rthres[0] and rdiff[i,j] >= self.rthres[1]:
                            rdiff[i,j] = self.rw[1]
                        elif rdiff[i,j] < self.rthres[1] and rdiff[i,j] >= self.rthres[2]:
                            rdiff[i,j] = self.rw[2]
                        elif rdiff[i,j] < self.rthres[2]:
                            rdiff[i,j] = self.rw[3]
                weights = np.multiply(rdiff, self.dw)
                bnf_img[y,x] = np.sum(np.multiply(img_pad[y:y+5,x:x+5], weights[:,:])) / np.sum(weights)
        self.img = bnf_img
        return self.clipping() 

def roi_surf_data(df, vertex_colname, surf, hemisphere, roi_radius):
    '''
    uses wb_command -surface-geodesic-rois to build rois (3D files)
    then load and collasp that into 1D array
    '''
    ## right the L and R hemisphere vertices from the table out to temptxt
    with ciftify.utils.TempDir() as lil_tmpdir:
        ## write a temp vertex list file
        vertex_list = os.path.join(lil_tmpdir, 'vertex_list.txt')
        df.loc[df.hemi == hemisphere, vertex_colname].to_csv(vertex_list,sep='\n',index=False, header=False)

        ## from the temp text build - func masks and target masks
        roi_surf = os.path.join(lil_tmpdir,'roi_surf.func.gii')
        docmd(['wb_command', '-surface-geodesic-rois', surf,
            str(roi_radius),  vertex_list, roi_surf,
            '-overlap-logic', 'EXCLUDE'])
        rois_data = ciftify.niio.load_gii_data(roi_surf)

    ## multiply by labels and reduce to 1 vector
    vlabels = df[df.hemi == hemisphere].roiidx.tolist()
    rois_data = np.multiply(rois_data, vlabels)
    rois_data1D = np.max(rois_data, axis=1)

    return rois_data1D 

def __init__(self, images, labels, fake_data=False, one_hot=False):
    """Construct a DataSet. one_hot arg is used only if fake_data is true."""

    if fake_data:
      self._num_examples = 10000
      self.one_hot = one_hot
    else:
      assert images.shape[0] == labels.shape[0], (
          'images.shape: %s labels.shape: %s' % (images.shape,
                                                 labels.shape))
      self._num_examples = images.shape[0]

      # Convert shape from [num examples, rows, columns, depth]
      # to [num examples, rows*columns] (assuming depth == 1)
      assert images.shape[3] == 1
      images = images.reshape(images.shape[0],
                              images.shape[1] * images.shape[2])
      # Convert from [0, 255] -> [0.0, 1.0].
      images = images.astype(numpy.float32)
      images = numpy.multiply(images, 1.0 / 255.0)
    self._images = images
    self._labels = labels
    self._epochs_completed = 0
    self._index_in_epoch = 0 

def make_edge_smooth(dataset_name, img_size) :
    check_folder('./dataset/{}/{}'.format(dataset_name, 'trainB_smooth'))

    file_list = glob('./dataset/{}/{}/*.*'.format(dataset_name, 'trainB'))
    save_dir = './dataset/{}/trainB_smooth'.format(dataset_name)

    kernel_size = 5
    kernel = np.ones((kernel_size, kernel_size), np.uint8)
    gauss = cv2.getGaussianKernel(kernel_size, 0)
    gauss = gauss * gauss.transpose(1, 0)

    for f in tqdm(file_list) :
        file_name = os.path.basename(f)

        bgr_img = cv2.imread(f)
        gray_img = cv2.imread(f, 0)

        bgr_img = cv2.resize(bgr_img, (img_size, img_size))
        pad_img = np.pad(bgr_img, ((2, 2), (2, 2), (0, 0)), mode='reflect')
        gray_img = cv2.resize(gray_img, (img_size, img_size))

        edges = cv2.Canny(gray_img, 100, 200)
        dilation = cv2.dilate(edges, kernel)

        gauss_img = np.copy(bgr_img)
        idx = np.where(dilation != 0)
        for i in range(np.sum(dilation != 0)):
            gauss_img[idx[0][i], idx[1][i], 0] = np.sum(
                np.multiply(pad_img[idx[0][i]:idx[0][i] + kernel_size, idx[1][i]:idx[1][i] + kernel_size, 0], gauss))
            gauss_img[idx[0][i], idx[1][i], 1] = np.sum(
                np.multiply(pad_img[idx[0][i]:idx[0][i] + kernel_size, idx[1][i]:idx[1][i] + kernel_size, 1], gauss))
            gauss_img[idx[0][i], idx[1][i], 2] = np.sum(
                np.multiply(pad_img[idx[0][i]:idx[0][i] + kernel_size, idx[1][i]:idx[1][i] + kernel_size, 2], gauss))

        cv2.imwrite(os.path.join(save_dir, file_name), gauss_img) 

def get_uv(self, xyz_vec):
        # Extract lens parameters of interest.
        fov_rad = self.lens.fov_deg * pi / 180
        fov_scale = np.float32(2 * self.lens.radius_px / fov_rad)
        # Normalize the input vector and rotate to match lens reference axes.
        xyz_rot = get_rotation_matrix(self.lens.center_qq) * matrix_norm(xyz_vec)
        # Convert to polar coordinates relative to lens boresight.
        # (In lens coordinates, unit vector's X axis gives boresight angle;
        #  normalize Y/Z to get a planar unit vector for the bearing.)
        # Note: Image +Y maps to 3D +Y, and image +X maps to 3D +Z.
        theta_rad = np.arccos(xyz_rot[0,:])
        proj_vec = matrix_norm(np.concatenate((xyz_rot[2,:], xyz_rot[1,:])))
        # Fisheye lens maps 3D angle to focal-plane radius.
        # TODO: Do we need a better model for lens distortion?
        rad_px = theta_rad * fov_scale
        # Convert back to focal-plane rectangular coordinates.
        uv = np.multiply(rad_px, proj_vec) + self.lens.center_px
        return np.asarray(uv + 0.5, dtype=int)

    # Given an 2xN array of UV pixel coordinates, check if each pixel is
    # within the fisheye field of view. Returns N-element boolean mask. 

def add_pixels(self, uv_px, img1d, weight=None):
        # Lookup row & column for each in-bounds coordinate.
        mask = self.get_mask(uv_px)
        xx = uv_px[0,mask]
        yy = uv_px[1,mask]
        # Update matrix according to assigned weight.
        if weight is None:
            img1d[mask] = self.img[yy,xx]
        elif np.isscalar(weight):
            img1d[mask] += self.img[yy,xx] * weight
        else:
            w1 = np.asmatrix(weight, dtype='float32')
            w3 = w1.transpose() * np.ones((1,3))
            img1d[mask] += np.multiply(self.img[yy,xx], w3[mask])


# A panorama image made from several FisheyeImage sources.
# TODO: Add support for supersampled anti-aliasing filters. 

def get_prediction(data, w0, w, v):
    """预测值

    :param data: 特征
    :param w0: 一次项权重
    :param w: 常数项权重
    :param v: 交叉项权重
    :return: 预测结果
    """
    m = np.shape(data)[0]
    result = []
    for x in range(m):
        inter_1 = data[x] * v
        inter_2 = np.multiply(data[x], data[x]) * np.multiply(v, v)
        inter = np.sum(np.multiply(inter_1, inter_1) - inter_2) / 2.
        p = w0 + data[x] * w + inter
        pre = sigmoid(p[0, 0])
        result.append(pre)
    return result 

def cost(theta, X, y, learningRate):
    theta = np.matrix(theta)
    X = np.matrix(X)
    y = np.matrix(y)
    first = np.multiply(-y, np.log(sigmoid(X * theta.T)))
    second = np.multiply((1 - y), np.log(1 - sigmoid(X * theta.T)))
    reg = (learningRate / (2 * len(X))) * np.sum(np.power(theta[:,1:theta.shape[1]], 2))
    return np.sum(first - second) / len(X) + reg 

def gradient(theta, X, y, learningRate):
    theta = np.matrix(theta)
    X = np.matrix(X)
    y = np.matrix(y)
    
    parameters = int(theta.ravel().shape[1])
    error = sigmoid(X * theta.T) - y
    
    grad = ((X.T * error) / len(X)).T + ((learningRate / len(X)) * theta)
    
    # intercept gradient is not regularized
    grad[0, 0] = np.sum(np.multiply(error, X[:,0])) / len(X)
    
    return np.array(grad).ravel() 

def sigmoid_gradient(z):
    return np.multiply(sigmoid(z), (1 - sigmoid(z))) 

def gradientDescent(X, y, theta, alpha, iters):
    temp = np.matrix(np.zeros(theta.shape))
    parameters = int(theta.ravel().shape[1])
    cost = np.zeros(iters)

    for i in range(iters):
        error = (X * theta.T) - y

        for j in range(parameters):
            term = np.multiply(error, X[:, j])
            temp[0,j] = theta[0,j] - ((alpha / len(X)) * np.sum(term))
        
        theta = temp
        cost[i] = computeCost(X, y, theta)
    return theta, cost 

def cost0(params, Y, R, num_features):
    Y = np.matrix(Y)  # (1682, 943)
    R = np.matrix(R)  # (1682, 943)
    num_movies = Y.shape[0]
    num_users = Y.shape[1]
    
    # reshape the parameter array into parameter matrices
    X = np.matrix(np.reshape(params[:num_movies * num_features], (num_movies, num_features)))  # (1682, 10)
    Theta = np.matrix(np.reshape(params[num_movies * num_features:], (num_users, num_features)))  # (943, 10)
    
    # initializations
    J = 0
    X_grad = np.zeros(X.shape)  # (1682, 10)
    Theta_grad = np.zeros(Theta.shape)  # (943, 10)
    
    # compute the cost
    error = np.multiply((X * Theta.T) - Y, R)  # (1682, 943)
    squared_error = np.power(error, 2)  # (1682, 943)
    J = (1. / 2) * np.sum(squared_error)
    
    # calculate the gradients
    X_grad = error * Theta
    Theta_grad = error.T * X
    
    # unravel the gradient matrices into a single array
    grad = np.concatenate((np.ravel(X_grad), np.ravel(Theta_grad)))
    
    return J, grad 

def cost1(params, Y, R, num_features, learning_rate):
    Y = np.matrix(Y)  # (1682, 943)
    R = np.matrix(R)  # (1682, 943)
    num_movies = Y.shape[0]
    num_users = Y.shape[1]
    
    # reshape the parameter array into parameter matrices
    X = np.matrix(np.reshape(params[:num_movies * num_features], (num_movies, num_features)))  # (1682, 10)
    Theta = np.matrix(np.reshape(params[num_movies * num_features:], (num_users, num_features)))  # (943, 10)
    
    # initializations
    J = 0
    X_grad = np.zeros(X.shape)  # (1682, 10)
    Theta_grad = np.zeros(Theta.shape)  # (943, 10)
    
    # compute the cost
    error = np.multiply((X * Theta.T) - Y, R)  # (1682, 943)
    squared_error = np.power(error, 2)  # (1682, 943)
    J = (1. / 2) * np.sum(squared_error)
    
    # add the cost regularization
    J = J + ((learning_rate / 2) * np.sum(np.power(Theta, 2)))
    J = J + ((learning_rate / 2) * np.sum(np.power(X, 2)))
    
    # calculate the gradients with regularization
    X_grad = (error * Theta) + (learning_rate * X)
    Theta_grad = (error.T * X) + (learning_rate * Theta)
    
    # unravel the gradient matrices into a single array
    grad = np.concatenate((np.ravel(X_grad), np.ravel(Theta_grad)))
    
    return J, grad 

def cost(theta, X, y):
    theta = np.matrix(theta)
    X = np.matrix(X)
    y = np.matrix(y)
    first = np.multiply(-y, np.log(sigmoid(X * theta.T)))
    second = np.multiply((1 - y), np.log(1 - sigmoid(X * theta.T)))
    return np.sum(first - second) / (len(X)) 

def costReg(theta, X, y, learningRate):
    theta = np.matrix(theta)
    X = np.matrix(X)
    y = np.matrix(y)
    first = np.multiply(-y, np.log(sigmoid(X * theta.T)))
    second = np.multiply((1 - y), np.log(1 - sigmoid(X * theta.T)))
    reg = (learningRate / (2 * len(X))) * np.sum(np.power(theta[:,1:theta.shape[1]], 2))
    return np.sum(first - second) / len(X) + reg 

def sub_events(bids_dir, sub_metadata, preproc_file,
               bids_events_fname=bids_events_fname):
    events_file = bids_dir.ensure(bids_events_fname)
    # read in subject metadata to get the TR
    with open(str(sub_metadata), 'r') as md:
        bold_metadata = json.load(md)
    tr = bold_metadata["RepetitionTime"]
    # time_points
    tp = nib.load(str(preproc_file)).shape[-1]
    # create voxel timeseries
    task_onsets = np.zeros(tp)
    # add waffles at every 40 time points
    task_onsets[0::40] = 1
    # add fries at every 40 time points starting at 3
    task_onsets[3::40] = 1
    # add milkshakes at every 40 time points starting at 6
    task_onsets[6::40] = 1
    # create event tsv
    num_trials = np.where(task_onsets == 1)[0].shape[0]
    onsets = np.multiply(np.where(task_onsets == 1), tr).reshape(num_trials)
    durations = [1] * num_trials
    num_conds = 3
    trial_types = ['waffle', 'fry', 'milkshake'] * int((num_trials / num_conds))
    events_df = pd.DataFrame.from_dict({'onset': onsets,
                                        'duration': durations,
                                        'trial_type': trial_types})
    # reorder columns
    events_df = events_df[['onset', 'duration', 'trial_type']]
    # save the events_df to file
    events_df.to_csv(str(events_file), index=False, sep='\t')
    return events_file 

def get_guided_grad_cam(cam, imggrad):
    """Compute Guided Grad-CAM. Refer section 3 of https://arxiv.org/abs/1610.02391 for details"""
    return np.multiply(cam, imggrad) 

def _get_mask(self, idx, in_data):
        """Returns the mask by which to multiply the parts of the embedding layer.
        In this version, we have no weights to apply.
        """
        mask = idx >= 0  # bool False for -1 values that should be removed. shape=(b,mnz)
        mask = np.expand_dims(mask,2) # shape = (b,mnz,1)
        mask = np.repeat(mask, self._proj_dim, axis=2) # shape = (b,mnz,d)
        return mask 

def forward(self, is_train, req, in_data, out_data, aux):
        #Note: see this run in notebooks/howto-numpy-random-proj.ipynb
        # Notation for shapes: b = batch_size, mnz = max_nonzero, d = proj_dim
        idx = in_data[0].asnumpy().astype('int32') # shape=(b,mnz)

        wd = self.W[idx]  # shape= (b,mnz,d)
        mask = self._get_mask(idx, in_data)
        wd = np.multiply(wd,mask)  # shape=(b,mnz,d), but zero'd out non-masked
        y = np.sum(wd,axis=1)  # shape=(b,d)
        mxy = mx.nd.array(y)  #NOTE: this hangs if the environment variables aren't set correctly
        # See https://github.com/dmlc/mxnet/issues/3813
        self.assign(out_data[0], req[0], mxy) 

def sampler(mu, logvar):
        z = mu + np.multiply(np.exp(0.5*logvar), np.random.normal(loc=0, scale=1,size=np.shape(logvar)))
        return z