Day 2: 30-days to learn rgl, plotly, and gganimate - Explore plotly customizations: add labels, hover effects, adjust colors, and practice layout modifications

 

Step 1: Set Up the Basic Plot

We’ll start by creating a simple scatter plot that we’ll customize throughout this tutorial.

1.     Create a Sample Dataset:

# Sample data

x <- c(1, 2, 3, 4, 5)

y <- c(10, 15, 13, 17, 20)

labels <- c("A", "B", "C", "D", "E")

2.     Generate the Basic Scatter Plot:

library(plotly)

# Basic scatter plot

plot <- plot_ly(x = ~x, y = ~y, type = 'scatter', mode = 'markers')

plot

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Step 2: Add Labels

You can add custom labels for each point to provide additional context.

1.     Add Labels as Text:

plot <- plot_ly(x = ~x, y = ~y, text = ~labels, type = 'scatter', mode = 'markers+text') %>%

  layout(title = "Scatter Plot with Labels",

         xaxis = list(title = "X Axis"),

         yaxis = list(title = "Y Axis"))

plot

• Explanation:
• text = ~labels: Adds text labels from the labels variable.
• mode = 'markers+text': Displays both markers and text.

2.     Adjust Text Position:

plot <- plot %>%

  layout(title = "Scatter Plot with Custom Label Positions") %>%

  style(textposition = 'top right')  # Try 'top left', 'bottom right', etc.

plot

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Step 3: Add and Customize Hover Effects

Hover effects can be customized to display more detailed information.

1.     Customize Hover Text:

plot <- plot_ly(x = ~x, y = ~y, text = ~paste("Point:", labels, "<br>X:", x, "<br>Y:", y),

                hoverinfo = 'text', type = 'scatter', mode = 'markers') %>%

  layout(title = "Scatter Plot with Customized Hover Text")

plot

• Explanation:
• hoverinfo = 'text': Specifies that hover text should come from the text argument.
• paste() function with <br>: Adds HTML line breaks to format the hover text neatly.

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Step 4: Adjust Colors

Colors can make plots visually appealing and help convey information.

1.     Change Marker Colors:

plot <- plot_ly(x = ~x, y = ~y, text = ~labels, type = 'scatter', mode = 'markers',

                marker = list(color = 'blue', size = 10)) %>%

  layout(title = "Scatter Plot with Custom Marker Color")

plot

2.     Add Conditional Colors:

# Set colors based on y values

colors <- c("red", "green", "blue", "orange", "purple")

plot <- plot_ly(x = ~x, y = ~y, text = ~labels, type = 'scatter', mode = 'markers',

                marker = list(color = colors, size = 10)) %>%

  layout(title = "Scatter Plot with Conditional Colors")

plot

3.     Use a Color Gradient:

plot <- plot_ly(x = ~x, y = ~y, text = ~labels, type = 'scatter', mode = 'markers',

                marker = list(color = ~y, colorscale = 'Viridis', size = 10)) %>%

  layout(title = "Scatter Plot with Gradient Colors")

plot

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Step 5: Customize Layout

plotly offers extensive layout options to adjust axes, titles, legends, and background.

1.     Modify Title and Axis Titles:

plot <- plot %>%

  layout(title = list(text = "Customized Scatter Plot", font = list(size = 20, color = "darkblue")),

         xaxis = list(title = "Custom X Axis", titlefont = list(size = 15, color = "darkred")),

         yaxis = list(title = "Custom Y Axis", titlefont = list(size = 15, color = "darkgreen")))

plot

2.     Customize Legend:

# Adding a legend and customizing its position and appearance

plot <- plot %>%

  layout(showlegend = TRUE, legend = list(x = 1, y = 1, font = list(size = 10, color = "black")))

plot

3.     Change Background Color:

plot <- plot %>%

  layout(plot_bgcolor = 'lightgrey',  # Background color of the plot area

         paper_bgcolor = 'lavender')  # Background color of the paper

plot

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Step 6: Combine All Customizations

Let’s put together everything we learned to create a fully customized scatter plot.

plot <- plot_ly(x = ~x, y = ~y, text = ~paste("Label:", labels, "<br>X:", x, "<br>Y:", y),

                hoverinfo = 'text', type = 'scatter', mode = 'markers+text',

                marker = list(color = ~y, colorscale = 'Viridis', size = 15)) %>%

  layout(title = list(text = "Fully Customized Scatter Plot", font = list(size = 22, color = "darkblue")),

         xaxis = list(title = "Custom X Axis", titlefont = list(size = 15, color = "darkred")),

         yaxis = list(title = "Custom Y Axis", titlefont = list(size = 15, color = "darkgreen")),

         plot_bgcolor = 'lightgrey',

         paper_bgcolor = 'lavender',

         legend = list(x = 1, y = 1, font = list(size = 10, color = "black")))

plot

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Summary

Today, you:

• Added text labels and customized their position.
• Created hover text with detailed information and used HTML for formatting.
• Customized colors, including conditional colors and gradients.
• Modified layout elements such as titles, axis labels, background color, and legend position.

Next, you’ll practice 3D plotting and explore deeper interactions to make your plots even more dynamic.