SAS.GRAPH 9.1 Reference, Volumes I and II
Overview
The GBARLINE procedure produces bar line charts. Bar line charts are vertical bar charts with a plot overlay. These charts graphically represent the value of a statistic calculated for one or more variables in an input SAS data set. The charted variables can be either numeric or character.
The procedure calculates these statistics:
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frequency or cumulative frequency counts
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percentages or cumulative percentages
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sums
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means.
Use the GBARLINE procedure to
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display and compare exact and relative magnitudes
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examine the contribution of parts to the whole
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analyze where data are out of balance
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display long series of data, showing trends and patterns.
In conjunction with the SYMBOL statement, the GBARLINE procedure can produce needle plot overlays, and overlay plots with stepped interpolation.
Note: PROC GBARLINE is not supported by Java.
About Bar Line Charts
Bar line charts display the magnitude of data with bars, each of which represents a category of data (midpoint). The height of the bars represents the value of the bar statistic for the corresponding midpoint .
Figure 28.1 on page 740 shows the relationship between petal width and petal length for three species of flowers. The horizontal axis is the midpoint axis and the vertical axes are response axes. Each axis is labeled with the variable name . Each species is a midpoint, so each bar is labeled with the species identifier.
About Interpolation Methods
You can produce plot overlays such as needle plot overlays by specifying interpolation methods with the SYMBOL statement. For PROC GBARLINE, you can use the SYMBOL statement to
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connect the data points to the zero line on the vertical axis (NEEDLE)
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use a step function to connect the data points (STEP)
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produce overlay plots with unconnected data points (NONE)
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connect data points with straight lines (JOIN).
For bar line graphs, points on the plot overlay are automatically joined, which is equivalent to specifying the JOIN interpolation method.
SYMBOL Statement on page 183 describes the JOIN, NEEDLE, STEP, and NONE interpolation methods.