A list of all the posts and pages found on the site. For you robots out there is an XML version available for digesting as well.
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Fresh Ubuntu 24.04 to a smooth SV660N/MS1 spin: wire the holding brake 24 V, build IgH with –disable-eoe, ROS 2 Jazzy + motor_drive, reach panel _88rn, run a soft CSP demo, and stop without EE081.
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| On Dell Latitude 5501, smbios-battery-ctl can read charge limits but cannot set them. Use Dell Command | Configure (cctk) to write Custom:50-80 to the EC. |
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Turn off Clash Verge Rev update checks by setting auto_check_update: false in verge.yaml — a setting the GUI does not expose.
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SV660N 5-digit keypad: decode _28ry / AL blink, and panel-as-read faults (E6200, E6400, EE083) mapped to CoE 0x603F/0x203F.
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Standard Python virtual environments hide ROS 2 apt packages from colcon. Use –system-site-packages so pip stays isolated while builds can still import em, catkin_pkg, and friends.
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GRUB splits reading and writing the saved boot entry across GRUB_DEFAULT and GRUB_SAVEDEFAULT. That flexibility helps admins and automation, but it exposes mechanism instead of user intent—and nested configfile menus can silently break remember-last-selection.
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Install ubuntu-realtime on Ubuntu 24.04 with Intel + NVIDIA hybrid graphics: why apt stalls at 2%, why NVIDIA DKMS fails against PREEMPT_RT, how to finish dpkg, and how to restore nvidia-smi on the generic kernel only.
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Use a Nautilus Python extension to put Open in VS Code on right-click for files, folders, and empty folder backgrounds.
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When an agent cannot type a sudo password into a TTY, a short zenity askpass helper unlocks a stable sudo -A workflow.
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How I reclaimed about 2.8 GB from /var/lib/snapd/snaps on Ubuntu 24.04 by removing disabled Snap revisions and unused GNOME platform snaps.
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Shared learning notes for Nise Control Systems Engineering 7th Edition — review questions with my answers and LLM answers side by side.
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How I diagnosed a misleading llvmpipe report on Ubuntu Wayland and fixed the real Xwayland/GLX fallback by updating Xwayland and Xorg core packages.
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Clash Verge TUN mode is useful because it gives you system-wide proxying without configuring every application separately.
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I tried to reduce suspend battery drain on my Dell Latitude 5501 running Ubuntu 24.04.
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BaiduPCS-Go is a command-line Baidu Netdisk client.
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Current LLMs are already useful, but they still have several hard limits.
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Sometimes the Codex extension in VS Code can get stuck even though the Codex CLI still works normally.
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Sometimes the normal Git server is temporarily unavailable, but you still need to move work between two machines on the same local network.
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在中国使用 VFS 签证预约系统时，如果 Cloudflare 验证加载很慢、页面经常卡死或登录被临时锁定，可以先尝试把 DNS 改成 1.1.1.1 和 8.8.8.8。
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Linux 版微信在 Ubuntu 中没有内置的显示/隐藏窗口快捷键，可以用 xdotool 和 GNOME 自定义快捷键实现一个类似的切换功能。
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BLE random device addresses encode their address type in the two most significant bits of the random address.
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How installing the proprietary NVIDIA driver fixed repeated XWayland CPU spikes when launching Electron and Chromium apps on an Ubuntu 24.04 Intel + NVIDIA hybrid laptop.
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macOS 下遇到一个 WeType 的奇怪问题：切换到繁体输入后，再切回简体输入，有些字仍然会按繁体输出，例如 還、總、覆 这类结果会残留在简体模式里。
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I ran into a GitLab outage in a Docker-based deployment where the web UI returned 502 Bad Gateway, even though the container itself was still running and even showed as healthy in docker ps.
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If you regularly switch between branches, keep separate runtime environments, or want AI agents to work without disturbing your main checkout, a bare repository plus git worktree is one of the cleanest setups.
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Quick notes for running a WireGuard tunnel on an Apple Silicon Mac with wg-quick and launchd.
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If you set PasswordAuthentication no in sshd_config and SSH still accepts a password, the problem is usually not your keys. The problem is that OpenSSH can still allow password-like login through KbdInteractiveAuthentication, often backed by PAM.
prefix_rule for git is not usable Published:
Quick note from testing codex cli 0.119.0 on Windows: prefix_rule was not practical for allowing common git commands in a reusable way.
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Quick notes for setting up the Windows OpenSSH server from the OpenSSH-Win64.zip package.
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These are rules to reread, not slogans to admire.
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Calling hierarchies for computing homography (H), fundamental matrix (F), essential matrix (E), and bundle adjustment (BA) in OpenCV.
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Why gold-standard geometric error and symmetric transfer error differ, and when each is appropriate for evaluation and optimization.
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Why a circle becomes an ellipse after affine distortion, and how that ellipse (or two known length ratios) provides the two constraints needed for metric rectification.
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Exploring the applications and intuitive understanding of planar homologies in projective geometry, computer vision, and geometric transformations.
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An analysis of the systemic problems in China’s math education system, examining what works and what doesn’t, and comparing approaches with other countries.
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A collection of command-line scripts and tools for managing virtual machines using Libvirt, KVM, and QEMU, covering common VM operations, automation, and best practices.
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A guide to resolving OpenGL/EGL initialization and rendering issues when running ORB-SLAM3 in Docker containers on hosts with NVIDIA GPUs, covering proper GPU passthrough, EGL context setup, and common pitfalls.
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Learn how to quickly create a new terminal in Jupyter using a custom keyboard shortcut. This is especially useful for developers who frequently need to run shell commands while working in Jupyter notebooks.
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A comprehensive Docker setup for bioinformatics work, featuring non-root user configuration, Python virtual environments, R with Seurat, and Jupyter Lab with multi-profile docker-compose support.
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The term ‘HAL’ means different things in different domains—from kernel-level platform abstraction to application-level sensor control. Understanding these differences helps clarify domain-specific architecture choices.
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The HAL is not necessarily a module — it’s a boundary of responsibility between hardware-dependent and hardware-independent code.
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Quick notes to make a Cursor AppImage launchable from your desktop menus and include a proper icon.
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Having builds fail with:
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GraphHopper makes a deliberate design choice: paths are represented by edges, not nodes. This matters for correctness (turn restrictions/costs), fidelity (multiple parallel edges between the same nodes), and efficiency (edge properties drive routing).
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Install arm64 package directly in x86 ubuntu for cross compile.
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Some chats from ChatGPT
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Why use a multinomial function to get the next word prediction in a GPT (generative) model rather than outputting the id with the largest probability?
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Ubuntu下使用WPS, LibreOffice编辑文档、演示稿时，发现Ubuntu自带的（免费）字体丑。同样的文档在Windows，MAC下看着没问题，在Ubuntu下排版都乱了（字体宽度不一样）。将Windows的中文字体拷过来就好了。
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Fundamental Theorem of Linear Programming Given a linear program in standard form where A is an m × n matrix of rank m,
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Python demo of Figure 2.16 Sparse Error Correction via Logan’s Phenomenon from High-Dimensional Data Analysis with Low-Dimensional Models - John Wright, Yi Ma, Page 65
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Problem summary of High-Dimensional Data Analysis with Low-Dimensional Models - John Wright, Yi Ma
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Python implementation of Algorithm L1-Minimization by Projected Subgradient from High-Dimensional Data Analysis with Low-Dimensional Models - John Wright, Yi Ma, Page 63
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Let \(A\) be a matrix with size \(m \times n\). We want to project point z onto a plane \(\begin{align} \arg \min_{x} \lVert z-x \rVert_2 \\ \text{s.t. } Ax = y \end{align}\)
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Python implementation of Algorithm L0-Minimization by Exhaustive Search from High-Dimensional Data Analysis with Low-Dimensional Models - John Wright, Yi Ma, Page 48
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使用qemu运行arm docker模拟器，在模拟器中使用apt安装依赖后，将docker容器文件系统导出，作为cmake的sysroot，避免编译依赖。本文以ROS2为例，但方法并不限于ROS2
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Nhatrang