The time series in a certain period of time constitutes a K-line (Japanese candle chart), and a single K-line is called a bar line.

If it is a ticking sequence within one minute, it constitutes a minute K line, also known as a minute bar line;

If it is a minute sequence in a day, it constitutes a daily K-line, also known as a daily bar;

The schematic diagram of the bar is as follows:

Bar line is a data unit formed by the change of price in time dimension and space dimension. As shown in the figure below, a time series bar chart composed of multiple data units.

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