pandas.melt() is used to convert wide format data into long format. The answer is to define new column names by specifying id_vars retain the identification column, value_vars select the column to be melted, var_name and value_name, 1.id_vars='Name' means that the Name column remains unchanged, 2.value_vars=['Math','English','Science'] specifies the column to be melted, 3.var_name='Subject' sets the new column name of the original column name, 4.value_name='Score' sets the new column name of the original value, and finally generates three columns including Name, Subject and Score.

Pythoncanbeoptimizedformemory-boundoperationsbyreducingoverheadthroughgenerators,efficientdatastructures,andmanagingobjectlifetimes.First,usegeneratorsinsteadofliststoprocesslargedatasetsoneitematatime,avoidingloadingeverythingintomemory.Second,choos

Install pyodbc: Use the pipinstallpyodbc command to install the library; 2. Connect SQLServer: Use the connection string containing DRIVER, SERVER, DATABASE, UID/PWD or Trusted_Connection through the pyodbc.connect() method, and support SQL authentication or Windows authentication respectively; 3. Check the installed driver: Run pyodbc.drivers() and filter the driver name containing 'SQLServer' to ensure that the correct driver name is used such as 'ODBCDriver17 for SQLServer'; 4. Key parameters of the connection string

Installing macOS to VMwareFusion virtual machine requires preparation tools and the correct steps. 1. Prepare macOS computer, VMwareFusion (recommended Pro version), legal macOS installation images and Unlocker tools; 2. Select the correct system type when creating a virtual machine and allocate disks, memory and CPU reasonably; 3. If it cannot be started, use Unlocker to patch to support macOS; 4. If there is a black screen, formatting problem or network failure during the installation process, you can solve it by adjusting the monitor settings, formatting the disk and configuring the network mode; 5. After the installation is completed, install VMwareTools in time and optimize the settings, including shared folders, fixed resolutions and system updates.

First, define a ContactForm form containing name, mailbox and message fields; 2. In the view, the form submission is processed by judging the POST request, and after verification is passed, cleaned_data is obtained and the response is returned, otherwise the empty form will be rendered; 3. In the template, use {{form.as_p}} to render the field and add {%csrf_token%} to prevent CSRF attacks; 4. Configure URL routing to point /contact/ to the contact_view view; use ModelForm to directly associate the model to achieve data storage. DjangoForms implements integrated processing of data verification, HTML rendering and error prompts, which is suitable for rapid development of safe form functions.

Introduction to Statistical Arbitrage Statistical Arbitrage is a trading method that captures price mismatch in the financial market based on mathematical models. Its core philosophy stems from mean regression, that is, asset prices may deviate from long-term trends in the short term, but will eventually return to their historical average. Traders use statistical methods to analyze the correlation between assets and look for portfolios that usually change synchronously. When the price relationship of these assets is abnormally deviated, arbitrage opportunities arise. In the cryptocurrency market, statistical arbitrage is particularly prevalent, mainly due to the inefficiency and drastic fluctuations of the market itself. Unlike traditional financial markets, cryptocurrencies operate around the clock and their prices are highly susceptible to breaking news, social media sentiment and technology upgrades. This constant price fluctuation frequently creates pricing bias and provides arbitrageurs with

The core methods of secure access to Binance official website are: 1. Manually enter the official website and add bookmarks; 2. Verify the lock icon and HTTPS in the browser address bar; 3. Avoid clicking on links in search engines, social media or unknown messages. When downloading a new version of the application, the desktop should be downloaded from the official website, iOS users should go through the App Store, and Android users should choose Google Play. If you cannot access it, you must download it through the verified official website. Always enable two-factor verification and be alert to false customer service information to ensure your account is secure.

iter() is used to obtain the iterator object, and next() is used to obtain the next element; 1. Use iterator() to convert iterable objects such as lists into iterators; 2. Call next() to obtain elements one by one, and trigger StopIteration exception when the elements are exhausted; 3. Use next(iterator, default) to avoid exceptions; 4. Custom iterators need to implement the __iter__() and __next__() methods to control iteration logic; using default values is a common way to safe traversal, and the entire mechanism is concise and practical.