Adaptive filters are a type of filter that does not belong to traditional low-pass, high-pass, band-pass, or band-stop filters. They can automatically adjust the filtering effect based on market volatility and periodicity. This type of filter provides a more flexible and intelligent tool to help us better understand and analyze market dynamics. John F. Ehlers has developed various adaptive technical indicators, such as the MESA Adaptive Moving Average (MAMA) and the Adaptive Laguerre filter, which can better adapt to market changes and provide more timely and accurate signals. Building an adaptive filter requires in-depth analysis of market data, understanding its inherent dynamics, and using this knowledge to dynamically adjust the filter's parameters.

This article introduces how to use derivatives to calculate the second, third, and fourth derivatives of prices, and explains their applications in the financial market. The first derivative represents the change in velocity, the second derivative represents the change in acceleration, the third derivative represents the change in the rate of change of acceleration, and the fourth derivative represents the change in the rate of change of acceleration. The article also discusses the characteristics of derivatives as high-pass filters and the differences in cutoff frequency and corner frequency for different orders of derivatives. Finally, the article mentions some popular technical indicators that use the concept of derivatives and emphasizes the need for smoothing or other processing techniques to reduce the impact of errors and noise in practical applications.

Any moving average is an oscillator, and a bandpass filter can be generated by combining low-pass and high-pass filters. Converting a low-pass filter to a bandpass filter is more practical, while converting a high-pass filter to a bandpass filter may not be as practical. The conversion process is irreversible. John F. Ehlers has developed many technical indicators based on digital signal processing, including low-pass, high-pass, and bandpass filters.

This article introduces the common types of filters used in technical analysis, including low-pass filters, high-pass filters, band-pass filters, and notch filters. Although pure notch filters are not commonly seen in technical indicators, some indicators, such as the high-low difference, can be approximately considered as having notch characteristics. Additionally, the article lists some common technical indicators and explains their relationship with filters.

This article tells the story of a black cat named Qingmao, who is passionate about invention and innovation, and explores the secrets of developing trading strategies on TradingView. The trading scripts are divided into five levels, ranging from simple open-source indicators to advanced subscription-based proprietary indicators. Qingmao invites readers to discuss and exchange these trading scripts and offers customized technical indicator development services. The ultimate goal is to achieve stable income in the world of quantitative trading through trading practice and improvement.

Strategy standardization entails the development of take-profit and stop-loss setups, the generation of signal alerts, and the implementation of a backtesting framework, all serving to provide an operational environment and safeguard for trading strategies. Bullets represent the generation of entry and exit points in trading strategies, while guns include the creation of profit and loss limits and signal alerts, with the battlefield representing the trading platform. Modular design enhances the system's flexibility, scalability, maintainability, and adaptability. The buy-sell point algorithm (bullets) is like a public key, while profit and loss limits and backtesting framework (guns) are like a private key, working together to form a complete trading system. The benefits of this design include security, flexibility, reusability, and maintainability. The modular trading system design is analogous to public key encryption and private key decryption in encrypted communication. This design improves the system's security, flexibility, reusability, and maintainability