bio-data-visualization-multipanel-figures

Version Compatibility

Reference examples tested with: ggplot2 3.5+, matplotlib 3.8+

Before using code patterns, verify installed versions match. If versions differ:

• Python: pip show <package> then help(module.function) to check signatures
• R: packageVersion('<pkg>') then ?function_name to verify parameters

If code throws ImportError, AttributeError, or TypeError, introspect the installed package and adapt the example to match the actual API rather than retrying.

Multi-Panel Figure Assembly

"Combine multiple plots into one figure" → Arrange subplots into a publication-ready multi-panel layout with shared legends and consistent sizing.

• R: patchwork::wrap_plots(), cowplot::plot_grid()
• Python: matplotlib.pyplot.subplots(), fig.add_subplot()

patchwork Basics

library(patchwork)

p1 <- ggplot(df, aes(x, y)) + geom_point()
p2 <- ggplot(df, aes(group, value)) + geom_boxplot()
p3 <- ggplot(df, aes(x)) + geom_histogram()

# Horizontal
p1 + p2 + p3

# Vertical
p1 / p2 / p3

# Mixed layouts
(p1 | p2) / p3
(p1 + p2) / (p3 + p4)

Panel Labels

# Automatic labels
(p1 + p2 + p3) + plot_annotation(tag_levels = 'A')

# Custom labels
(p1 + p2 + p3) + plot_annotation(tag_levels = list(c('A', 'B', 'C')))

# Label styling
(p1 + p2) + plot_annotation(
    tag_levels = 'A',
    tag_prefix = '(',
    tag_suffix = ')',
    theme = theme(plot.tag = element_text(face = 'bold', size = 14))
)

Layout Control

# Width ratios
p1 + p2 + plot_layout(widths = c(2, 1))

# Height ratios
p1 / p2 + plot_layout(heights = c(1, 2))

# Complex grid
layout <- "
AAB
AAB
CCC
"
p1 + p2 + p3 + plot_layout(design = layout)

# Fixed dimensions
p1 + p2 + plot_layout(widths = unit(c(5, 3), 'cm'))

Shared Legends

# Collect legends
(p1 + p2 + p3) + plot_layout(guides = 'collect')

# Position at bottom
(p1 + p2) + plot_layout(guides = 'collect') &
    theme(legend.position = 'bottom')

# Keep individual legends
(p1 + p2) + plot_layout(guides = 'keep')