addition

问题 There are 2 ways to merge lists together in Python: ['a', 'b', 'c'] + ['x', 'y', 'z'] ['a', 'b', 'c'].extend(['x', 'y', 'z']) What's the difference between the 2 methods? What's the more Pythonic way of concatenating more than 2 lists? ['a', 'b', 'c'] + [1, 2, 3] + ['x', 'y', 'z'] gucci_list = ['a', 'b', 'c'] gucci_list.extend([1, 2, 3]) gucci_list.extend(['x', 'y', 'z']) How about combining both? ['a', 'b', 'c'].extend([1, 2, 3] + ['x', 'y', 'z']) 回答1: The first statement creates a new list

问题 I'm starting on C# now. I had a problem in tackling a question my lecturer asked me to do. Below is the GUI. http://i.share.pho.to/daa36a24_c.png This is the code i did but i didn't manage to code part the i mentioned below using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace WindowsFormsApplication1 { public partial class Form1 : Form { public Form1() {

问题 Does anyone know the steps for dividing unsigned binary integers using non-restoring division? It's hard to find any good sources online. i.e if A = 101110 and B = 010111 how do we find A divided by B in non-restoring division? What do the registers look like in each step? Thanks! 回答1: (My answer is a little late-reply. But I hope it will be useful for future visitors) Algorithm for Non-restoring division is given in below image : In this problem, Dividend (A) = 101110, ie 46, and Divisor (B)

问题 Does anyone know the steps for dividing unsigned binary integers using non-restoring division? It's hard to find any good sources online. i.e if A = 101110 and B = 010111 how do we find A divided by B in non-restoring division? What do the registers look like in each step? Thanks! 回答1: (My answer is a little late-reply. But I hope it will be useful for future visitors) Algorithm for Non-restoring division is given in below image : In this problem, Dividend (A) = 101110, ie 46, and Divisor (B)

问题 I converted my csv file to text file and I want to add the numbers inside the text file. When I run my code get an error. Assuming the error code I want to write logic that would bypass my strings and just add the numeric values. `import csv csv_file = 'Annual Budget.csv' txt_file = 'annual_budget.txt' with open(txt_file, 'w') as my_output_file: with open(csv_file, 'r') as my_input_file: reader = csv.reader(my_input_file) for row in reader: my_output_file.write(" ".join(row)+'\n') data = []

问题 I'm having a hard time explaining this one. The following function is being used as a worksheet formula. A value of "empty" simply means that the cell was empty and, therefore, there is no value. Given the values {empty, empty, 0.8, 0.2}, the following function is sometimes returning off the wall values like 5.55111512312578E-17. In the debugger, it looks like everything is correct until the last value in the ParamArray (in this case 0.2) is processed. Any thoughts? Private Function

问题 I want to add values of 4 Dataframes with the same indexes in Pandas. If there are two dataframes, df1 and df2, we may write: df1.add(df2) and for 3 dataframes: df3.add(df2.add(df1)) I wonder if there is a more general way to do so in Python. 回答1: Option 1 Use sum sum([df1, df2, df3, df4]) Option 2 Use reduce from functools import reduce reduce(pd.DataFrame.add, [df1, df2, df3, df4]) Option 3 Use pd.concat and pd.DataFrame.sum with level=1 This only works if there is a single level to the

问题 I'm adding two vectors that I thought were 'reshaped' together and getting a 2d matrix as a result. I expect some type of error here, but didn't get it. I think I understand what's happening, it treated them as if there were two more sets of each vector horizontally and vertically, but I don't understand why the results of a and b aren't different. And if they're not meant to be, why does this work at all? import tensorflow as tf import numpy as np start_vec = np.array((83,69,45)) a = tf

问题 Is there a way to construct a vector as the concatenation of 2 vector s (Other than creating a helper function?) For example: const vector<int> first = {13}; const vector<int> second = {42}; const vector<int> concatenation = first + second; I know that vector doesn't have an addition operator like string , but that's the behavior that I want. Such that concatenation would contain: 13 and 42. I know that I can initialize concatenation like this, but it prevents me from making concatenation

问题 folks! I've encountered a little problem: I'm doing a simple addition with three double values. The result has a smaller precision than the used values. double minutes = 3; minutes = minutes / (24.0*60.0); // contains 0.00208333 double hours = 3; hours = hours / 24.0; // contains 0.125 double days = 3; // contains 3 double age = days + hours + minutes; // result is 3.12708 I found no way to avoid this behaviour. 回答1: Nothing seems to be wrong with the calculation as what the comments on your