There are many formulas for communication. Take the calculation formula of the highest price in a certain period as an example: ref(hhv(h, n), m); Formula meaning: Find the highest price between (N+M) days and the previous m days. For example: ref(hhv(h, 10),10); Find the highest price from 20 days ago to 10 days ago. Taking 15 days as an example, there are several related formulas: hhv(h,15) = h; {The highest price today is the highest price since 15 days}; ref(hhv(h， 15))= h； {The highest price today is the highest price on the previous15th day}; ref(hhv(c， 15))= h； {Today's highest price is the highest price of the previous 15 closing price}. I. What is a communication letter? Communication letter is one of the manufacturers providing online transactions in the national market. Citic, Guotai Junan, Huatai, Yinhe, CITIC Jiantou, Shenwan Hongyuan, Guo Xin, China Merchants, Haitong, Guangfa, Xingye, Zhongtai and Anxin have all adopted the online trading quotation system of Tongda Letter. Tongda letter's well-known online trading products include: China Merchants Securities Zhiyuan Yitong, Guosen Securities Golden Sun Edition, CITIC Securities Zhixin All-around Edition, Guangfa Securities Financial Terminal, Galaxy Securities Neptune Star, Guotai Junan Securities Fuyi, Everbright Securities Jinyang Guang Excellence Edition, CITIC Jiantou Securities Excellence Edition, Huatai Securities Advanced Edition, Zhongtai Securities Rongyihui, Industrial Securities Youlibao Wealth Edition, changjiang securities Jinchang Caizhi Edition, Admiralty Financial Terminal and Anxin Securities Anrui Edition. Guohai Securities Jintan, Founder Securities Xiaofang Edition, Ping An Securities Huiying Edition ... Tongdaxin stock trading software is a mobile securities software designed by Shenzhen Fortune Trend Technology Co., Ltd., which is positioned as a securities information platform providing multi-functional services. Communication allows users to divide the screen freely and specify the content corresponding to each block. 2. The function of Tong Daxin software is 1, which integrates the market conditions of Shanghai, Shenzhen, Hong Kong stocks, US stocks, futures, options, funds, macro and foreign exchange, and is suitable for all investors. 2. Innovatively combine the data of Shanghai and Shenzhen, and launch special functions such as DDE decision-making, individual stock capital flow, theme events, consensus expectation, shareholding change, and dragon and tiger list. 3. Provide market quotes of Shanghai, Shenzhen, Hong Kong and US stocks, and support self-selection, ranking, sectors and various technical indicators. 4. Summarize the global market through commodity futures, foreign exchange rate and global index. 5, with a variety of column information. Third, it is recommended not to use concentric software. On June 26th, 2020, 10 was notified by the Information and Communication Administration of the Ministry of Industry and Information Technology for rectification due to the illegal use of personal information. The Ministry of Industry and Information Technology inspected Tongxin Da and found that it illegally collected users' personal information and ordered it to rectify.