Bar, line and pie graphs are three types of graph that can be used to chart values. To consider each graph separately:
Bar graphs:
The bar graph is a graph that uses bars to represent values from a given range. Here, bars are plotted alongside two-axis so that values can be compared. These axis are referred to as the x, and y axis. The x -axis, runs horizontally, and is used to place the field values. Then, the y-axis is vertical and is used to plot the values on.
So, when beginning a bar graph these two-axis are first complete. Then, the values can be listed along the x-axis horizontally from one to another. From here, the y-axis scale can then be complete which must include the highest values from the fields. Then the bar can be plotted on the graph for each alongside the y-axis value.
Bar graphs are very good for comparing values. By using a bar graph, they can chart the disparities.
Line graphs:
Like the bar graphs, line graphs have two axis for the values. In fact the plotting is identical to bar graphs, however no bars are used. Instead the line graph plots dots on the graph, which can then be connected via straight lines. So overall, while the line graph is similar to bar graph it is not the same.
When a line graph is complete, the lines will identify any trends. They may be upwards or downwards for example.
Pie Graph (or chart):
The pie graph does not have an axis as such. Instead it is a circle which charts values. Usually, these are percentage value comparisons.
For a pie graph, all the values to be used are added. Then, 360 are divided by the total. This result is used to multiply the values by, which is the angle to use for the value.
An example: Two values, fifty and fifty are added equalling one hundred. Then 360 is divided by 100 which is 3.6. Fifty multiply by three-point-six is a 180-degree angle for each segment.
A protractor and ruler are then used for the pie chart angles. It is also good to shade the segments of the pie chart. In addition, a data table could be included.
Overall, the pie chart is good for percentages. Let us say that you have nine-golf holes scores. A pie chart will highlight the percentage number of strokes for each hole played.
So the bar, line and pie charts are three good graphs for charting data. While the line and bar graph are similar the pie chart is not. The most appropriate graph is the best graph.