Revision history [back]

To create a stacked bar graph with data from GridDB in R, you can use the ggplot2 package. Here are the steps:

1. First, you'll need to install and load the ggplot2 package:

install.packages("ggplot2")
library(ggplot2)

1. Next, you'll need to retrieve the data from GridDB. You can use the GridDB R client library to connect to your GridDB cluster and query the data. Here's an example:

library(griddb)

# Connect to the GridDB cluster
cluster <- griddb.connect("your_griddb_host", 31810, "your_username", "your_password")

# Query the data from the desired container
container <- cluster$put_container("container_name")
result_set <- container$query("SELECT column1, column2, column3 FROM container_name")

# Convert the result set to a data frame
data <- as.data.frame(result_set)

1. Once you have the data in a data frame, you can use ggplot2 to create the stacked bar graph. Here's an example:

ggplot(data, aes(x = column1, y = column2, fill = column3)) +
  geom_bar(stat = "identity") +
  labs(x = "X axis label", y = "Y axis label", fill = "Legend label") +
  theme(legend.position = "bottom") +
  guides(fill = guide_legend(ncol = 2))

Explanation of the code:

• The ggplot() function creates a new ggplot object, with the data argument specifying the data frame to use, and the aes() function specifying the mapping between data and aesthetic attributes.
• The geom_bar() function adds the bar chart layer to the ggplot object, with the stat = "identity" parameter specifying that the height of the bars should be the actual data values.
• The labs() function adds axis and legend labels to the plot.
• The theme() function sets the position of the legend to the bottom of the plot area.
• The guides() function specifies the number of columns to use for the legend.

1. If the legend is not being displayed in the graph, it might be due to some overlapping elements in the plot. You can try adjusting the size and position of the plot and legend, or reducing the number of categories in the fill variable.