Method and device for compressing flow data

A device for compressing flow data, comprising:

• a receiver, configured to acquire flow data and acquire a maximum error that is predefined, wherein the flow data comprises multiple data points, and each data point of the multiple data points comprises collection time of each data point and a data value collected at the collection time;
• a processor, configured to construct multiple line segments according to the multiple data points and the maximum error that are acquired by the receiver and determine a target piecewise linear function according to the multiple line segments, wherein the multiple line segments do not intersect with each other, each line segment of the multiple line segments represents a function with time as an independent variable, and when a value of the independent variable is the collection time, an absolute value of a difference between a function value of the function and the data value collected at the collection time is less than or equal to the maximum error, wherein the target piecewise linear function comprises multiple linear functions, and an intersection set of value ranges of independent variables of every two linear functions among the multiple linear functions comprises a maximum of one value;
• and
• a transmitter, configured to output a reference data point according to the target piecewise linear function determined by the obtaining unit, wherein the reference data point is used to represent compressed flow data, and the reference data point comprises a point of continuity and a point of discontinuity of the target piecewise linear function.