optimization

问题 So I have a list with several <li> elements, <ul> <li>a</li> <li>b</li> <li>c</li> <li>d</li> <li>e</li> <li>f</li> <li>g</li> <li>h</li> </ul> The context is I want to re-use li elements across a 1,000 memory intensive list for iOS. The objective is to display first 4 elements, the rest 4 are hidden, the container displays 4 items at a time. On scroll (button tap), I'm going to animate the list and slide in the other 4, and at the end of the animation, move the first 4 li items towards the

问题 I'm implementing the CSS3 flexible box layout module as defined by the W3C, which is similar to Mozilla's box model for xul. While these standards specify how the model should behave, they don't give any details on how they should be implemented. The parts of the model I'm interested in are: Boxes have a width and height. Boxes can contain other boxes. Container boxes (parent boxes) are responsible for sizing and positioning the boxes they contain (child boxes). Boxes have orientation which

问题 I reached a bottleneck in my code, so the main issue of this question is performance. I have a hexadecimal checksum and I want to check the leading zeros of an array of chars. This is what I am doing: bool starts_with (char* cksum_hex, int n_zero) { bool flag {true}; for (int i=0; i<n_zero; ++i) flag &= (cksum_hex[i]=='0'); return flag; } The above function returns true if the cksum_hex has n_zero leading zeros. However, for my application, this function is very expensive (60% of total time).

问题 English is not good, but please understand. string str; string str_base = "user name = "; string str_user_input; string str_system_message; ... str = str_base + str_user_input + "\n [system message :]" + str_system_message; cout << str << endl; I'm using the existing code like this, is there a way to optimize string? I think this code does a lot of useless operations. Is there a way to optimize? 回答1: Your question says +=, but you're not using += anywhere. You are using only +. "+" is

问题 I have an objective function which looks like: f1 = -1 * (constant1 * (variable1 - constant2)) And I have a constraint such that the function f1 should only take values between 10 to 20 i.e. 10 <= f1 <= 20 where, f1 = -1 * (constant1 * (variable1 - constant2)) How do I code the above constraints in pymoo optimisation problem. I'm not interested in the bounds because as I see from the documentation, bounds are only for defining limits on the input(x) values and not for defining the limits on

问题 I want to drag a PictureBox, and I have managed to do so. But my application doesn't do it as smoothly as Windows photo viewer. I mean the difference isn't huge or anything, but it's noticeable. Is there something I could do to make it a little less choppy? This is my simple code: int MOUSE_X = 0; int MOUSE_Y = 0; public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { picBox.Image = Image.FromFile(@"D:\test_big.png"); picBox.Width = 3300; picBox.Height

问题 I have an objective function which looks like: f1 = -1 * (constant1 * (variable1 - constant2)) And I have a constraint such that the function f1 should only take values between 10 to 20 i.e. 10 <= f1 <= 20 where, f1 = -1 * (constant1 * (variable1 - constant2)) How do I code the above constraints in pymoo optimisation problem. I'm not interested in the bounds because as I see from the documentation, bounds are only for defining limits on the input(x) values and not for defining the limits on

问题 I want to drag a PictureBox, and I have managed to do so. But my application doesn't do it as smoothly as Windows photo viewer. I mean the difference isn't huge or anything, but it's noticeable. Is there something I could do to make it a little less choppy? This is my simple code: int MOUSE_X = 0; int MOUSE_Y = 0; public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { picBox.Image = Image.FromFile(@"D:\test_big.png"); picBox.Width = 3300; picBox.Height

问题 I want to drag a PictureBox, and I have managed to do so. But my application doesn't do it as smoothly as Windows photo viewer. I mean the difference isn't huge or anything, but it's noticeable. Is there something I could do to make it a little less choppy? This is my simple code: int MOUSE_X = 0; int MOUSE_Y = 0; public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { picBox.Image = Image.FromFile(@"D:\test_big.png"); picBox.Width = 3300; picBox.Height

问题 For my project, I've written a naive C implementation of direct 3D convolution with periodic padding on the input. Unfortunately, since I'm new to C, the performance isn't so good... here's the code: int mod(int a, int b) { // calculate mod to get the correct index with periodic padding int r = a % b; return r < 0 ? r + b : r; } void convolve3D(const double *image, const double *kernel, const int imageDimX, const int imageDimY, const int imageDimZ, const int stencilDimX, const int stencilDimY