in a graph, why might the data be represented in horizontal line segments?
Lots of reasons. It depends upon what is plotted in the graph. You can get horizontal line segments in cases of
(1) distance vs. time during a peiod when a vehicle is not moving
(2) velocity vs. time during a period when a vehicle is not accelerating
(3) money in an account vs. time during a period of no deposits or withdrwals
(4) when you only have data on the amount of the dependent variable that corresponds to specific ranges of the independent variable. Such graphs are called histograms. For example: average income vs. age for age intervals of 20-30, 30-40, 50-60 etc.
so that it is clear too read and understand
The data might be represented in horizontal line segments in order to make it clear and easy to read and understand. When the data is displayed as horizontal line segments, it reduces the complexity of the graph and makes it easier to identify trends and patterns in the data.
By using horizontal line segments, the graph can quickly and clearly show situations where the value of the dependent variable remains constant over a certain range of the independent variable. This is particularly useful when there are multiple data points within that range.
For example, if you are plotting the distance traveled by a vehicle over time and there are periods when the vehicle is not moving, you would see a horizontal line segment at zero distance during those times. Similarly, if you are plotting the velocity of a vehicle over time and there is no acceleration during certain periods, you would see a horizontal line segment showing a constant velocity.
In other cases, when the data is divided into specific ranges of the independent variable, such as age intervals, a histogram is used. In a histogram, the frequency or amount of the dependent variable is represented by horizontal line segments corresponding to each interval of the independent variable.
Overall, representing the data in horizontal line segments helps in simplifying the graph and making it easier to comprehend the relationship between the variables being plotted.