R Visual – Create Gartner Magic Quadrant-Like Charts in Power BI using ggplot2

In this blog post, I am going to create a R visual that renders the Gartner magic quadrant-like charts in Power BI using the ggplot2 package.

2.PNG

A dummy dataset will be created, including three columns, the “Company” column holding the name of the companies which will be ranked in the quadrant chart, the “ExcutionScore” column and the “VisionScore” column corresponding to the “Ability to Execute” metric and the “Completeness of Vision” metric in the Gartner magic quadrant assessment. In the dummy dataset, the “ExcutionScore” and the “VisionScore” are scale from 0 to 100.

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We drag a R visual onto Power BI editor canvas and add the three columns from the dummy dataset. We can bind the RStudio IDE to Power BI and use it to author and test the R scripts.

In the R script editor, we first reference the “ggplot2” library and the “grid” library. The “grid” library is used to draw custom annotations outside of the main ggplot2 panel.

library(ggplot2)
library(grid)

We then create a ggplot2 object using the dataset referenced in the R visual, assigning the “VisionScore” value to x-axis and assigning the “ExcutionScore” value to y-axis.

p <- ggplot(dataset, aes(VisionScore, ExcutionScore))
p <- p + scale_x_continuous(expand = c(0, 0), limits = c(0, 100)) 
p <- p + scale_y_continuous(expand = c(0, 0), limits = c(0, 100))

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We now have our base panel and we can start our journey to build theĀ Gartner Magic Quadrant-Like chart.

First of all, we set the x-axis label as “COMPLETEMENT OF VISION” and set the y-axis label as “ABILITY TO EXECUTE” and make them aligned to left-side. We then remove the axis ticks and text from the plot. We will also add a title to the top of the plot.

p <- p + labs(x="COMPLETEMENT OF VISION",y="ABILITY TO EXECUTE")
p <- p + theme(axis.title.x = element_text(hjust = 0, vjust=4, colour="darkgrey",size=10,face="bold"))
p <- p + theme(axis.title.y = element_text(hjust = 0, vjust=0, colour="darkgrey",size=10,face="bold"))

p <- p + theme(
          axis.ticks.x=element_blank(), 
          axis.text.x=element_blank(),
          axis.ticks.y=element_blank(),
          axis.text.y=element_blank()
        )

p <- p + ggtitle("Gartner Magic Quadrant - Created for Power BI using ggpolt2") 

Those steps will progress our chart to somewhere like:

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We then add four rectangle type of annotations to fill the four quadrant areas using the Gartner magic quadrant scheme. We also need to create a border and split lines for the quadrant chart.

p <- p +
      annotate("rect", xmin = 50, xmax = 100, ymin = 50, ymax = 100, fill= "#F8F9F9")  + 
      annotate("rect", xmin = 0, xmax = 50, ymin = 0, ymax = 50 , fill= "#F8F9F9") + 
      annotate("rect", xmin = 50, xmax = 100, ymin = 0, ymax = 50, fill= "white") + 
      annotate("rect", xmin = 0, xmax = 50, ymin = 50, ymax = 100, fill= "white")

p <- p + theme(panel.border = element_rect(colour = "lightgrey", fill=NA, size=4))
p <- p + geom_hline(yintercept=50, color = "lightgrey", size=1.5)
p <- p + geom_vline(xintercept=50, color = "lightgrey", size=1.5)

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We also need to add a label to each quadrant area:

p <- p + geom_label(aes(x = 25, y = 97, label = "CALLENGERS"), 
                    label.padding = unit(2, "mm"),  fill = "lightgrey", color="white")
p <- p + geom_label(aes(x = 75, y = 97, label = "LEADERS"), 
                    label.padding = unit(2, "mm"), fill = "lightgrey", color="white")
p <- p + geom_label(aes(x = 25, y = 3, label = "NICHE PLAYERS"), 
                    label.padding = unit(2, "mm"),  fill = "lightgrey", color="white")
p <- p + geom_label(aes(x = 75, y = 3, label = "VISIONARIES"), 
                    label.padding = unit(2, "mm"), fill = "lightgrey", color="white")

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Up to this point, our chart starts to look like the Gartner magic quadrant. Next, we need to draw the company points to the chart with the position corresponding to their “Ability to Execute” value and “Completeness of Vision” value.

p <- p + geom_point(colour = "#2896BA", size = 5) 
p <- p  + geom_text(aes(label=Company),colour="#2896BA", hjust=-0.3, vjust=0.25, size=3.2)

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Our quadrant chart is nearly done, just one part missing, the arrows next to the “Ability to Execute” and “Completeness of Vision” text labels.

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As the arrows need to be located outside of the main panel, we need to create custom annotation (annotation_custom) with linesGrob to draw a straight line with an arrow at the far end of the line. To make the arrows to visible outside of the main panel, we need to turn off the clip attribute of the main panel.

p <- p + annotation_custom(
            grob = linesGrob(arrow=arrow(type="open", ends="last", length=unit(2,"mm")), 
                   gp=gpar(col="lightgrey", lwd=4)), 
            xmin = -2, xmax = -2, ymin = 25, ymax = 40
          )
p <- p + annotation_custom(
  grob = linesGrob(arrow=arrow(type="open", ends="last", length=unit(2,"mm")), 
                   gp=gpar(col="lightgrey", lwd=4)), 
  xmin = 28, xmax = 43, ymin = -3, ymax = -3
)

gt = ggplot_gtable(ggplot_build(p))
gt$layout$clip[gt$layout$name=="panel"] = "off"
grid.draw(gt)

We now have our completed quadrant chart.

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You can find the complete source code here:

Please find the pbix file here.

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