Scientific Visualization Overview
Scientific visualization transforms data into clear, accurate figures for publication. Create journal-ready plots with multi-panel layouts, error bars, significance markers, and colorblind-safe palettes. Export as PDF/EPS/TIFF using matplotlib, seaborn, and plotly for manuscripts.
When to Use This Skill
This skill should be used when:
Creating plots or visualizations for scientific manuscripts Preparing figures for journal submission (Nature, Science, Cell, PLOS, etc.) Ensuring figures are colorblind-friendly and accessible Making multi-panel figures with consistent styling Exporting figures at correct resolution and format Following specific publication guidelines Improving existing figures to meet publication standards Creating figures that need to work in both color and grayscale Quick Start Guide Basic Publication-Quality Figure import matplotlib.pyplot as plt import numpy as np
Apply publication style (from scripts/style_presets.py)
from style_presets import apply_publication_style apply_publication_style('default')
Create figure with appropriate size (single column = 3.5 inches)
fig, ax = plt.subplots(figsize=(3.5, 2.5))
Plot data
x = np.linspace(0, 10, 100) ax.plot(x, np.sin(x), label='sin(x)') ax.plot(x, np.cos(x), label='cos(x)')
Proper labeling with units
ax.set_xlabel('Time (seconds)') ax.set_ylabel('Amplitude (mV)') ax.legend(frameon=False)
Remove unnecessary spines
ax.spines['top'].set_visible(False) ax.spines['right'].set_visible(False)
Save in publication formats (from scripts/figure_export.py)
from figure_export import save_publication_figure save_publication_figure(fig, 'figure1', formats=['pdf', 'png'], dpi=300)
Using Pre-configured Styles
Apply journal-specific styles using the matplotlib style files in assets/:
import matplotlib.pyplot as plt
Option 1: Use style file directly
plt.style.use('assets/nature.mplstyle')
Option 2: Use style_presets.py helper
from style_presets import configure_for_journal configure_for_journal('nature', figure_width='single')
Now create figures - they'll automatically match Nature specifications
fig, ax = plt.subplots()
... your plotting code ...
Quick Start with Seaborn
For statistical plots, use seaborn with publication styling:
import seaborn as sns import matplotlib.pyplot as plt from style_presets import apply_publication_style
Apply publication style
apply_publication_style('default') sns.set_theme(style='ticks', context='paper', font_scale=1.1) sns.set_palette('colorblind')
Create statistical comparison figure
fig, ax = plt.subplots(figsize=(3.5, 3)) sns.boxplot(data=df, x='treatment', y='response', order=['Control', 'Low', 'High'], palette='Set2', ax=ax) sns.stripplot(data=df, x='treatment', y='response', order=['Control', 'Low', 'High'], color='black', alpha=0.3, size=3, ax=ax) ax.set_ylabel('Response (μM)') sns.despine()
Save figure
from figure_export import save_publication_figure save_publication_figure(fig, 'treatment_comparison', formats=['pdf', 'png'], dpi=300)
Core Principles and Best Practices 1. Resolution and File Format
Critical requirements (detailed in references/publication_guidelines.md):
Raster images (photos, microscopy): 300-600 DPI Line art (graphs, plots): 600-1200 DPI or vector format Vector formats (preferred): PDF, EPS, SVG Raster formats: TIFF, PNG (never JPEG for scientific data)
Implementation:
Use the figure_export.py script for correct settings
from figure_export import save_publication_figure
Saves in multiple formats with proper DPI
save_publication_figure(fig, 'myfigure', formats=['pdf', 'png'], dpi=300)
Or save for specific journal requirements
from figure_export import save_for_journal save_for_journal(fig, 'figure1', journal='nature', figure_type='combination')
- Color Selection - Colorblind Accessibility
Always use colorblind-friendly palettes (detailed in references/color_palettes.md):
Recommended: Okabe-Ito palette (distinguishable by all types of color blindness):
Option 1: Use assets/color_palettes.py
from color_palettes import OKABE_ITO_LIST, apply_palette apply_palette('okabe_ito')
Option 2: Manual specification
okabe_ito = ['#E69F00', '#56B4E9', '#009E73', '#F0E442', '#0072B2', '#D55E00', '#CC79A7', '#000000'] plt.rcParams['axes.prop_cycle'] = plt.cycler(color=okabe_ito)
For heatmaps/continuous data:
Use perceptually uniform colormaps: viridis, plasma, cividis Avoid red-green diverging maps (use PuOr, RdBu, BrBG instead) Never use jet or rainbow colormaps
Always test figures in grayscale to ensure interpretability.
- Typography and Text
Font guidelines (detailed in references/publication_guidelines.md):
Sans-serif fonts: Arial, Helvetica, Calibri Minimum sizes at final print size: Axis labels: 7-9 pt Tick labels: 6-8 pt Panel labels: 8-12 pt (bold) Sentence case for labels: "Time (hours)" not "TIME (HOURS)" Always include units in parentheses
Implementation:
Set fonts globally
import matplotlib as mpl mpl.rcParams['font.family'] = 'sans-serif' mpl.rcParams['font.sans-serif'] = ['Arial', 'Helvetica'] mpl.rcParams['font.size'] = 8 mpl.rcParams['axes.labelsize'] = 9 mpl.rcParams['xtick.labelsize'] = 7 mpl.rcParams['ytick.labelsize'] = 7
- Figure Dimensions
Journal-specific widths (detailed in references/journal_requirements.md):
Nature: Single 89 mm, Double 183 mm Science: Single 55 mm, Double 175 mm Cell: Single 85 mm, Double 178 mm
Check figure size compliance:
from figure_export import check_figure_size
fig = plt.figure(figsize=(3.5, 3)) # 89 mm for Nature check_figure_size(fig, journal='nature')
- Multi-Panel Figures
Best practices:
Label panels with bold letters: A, B, C (uppercase for most journals, lowercase for Nature) Maintain consistent styling across all panels Align panels along edges where possible Use adequate white space between panels
Example implementation (see references/matplotlib_examples.md for complete code):
from string import ascii_uppercase
fig = plt.figure(figsize=(7, 4)) gs = fig.add_gridspec(2, 2, hspace=0.4, wspace=0.4)
ax1 = fig.add_subplot(gs[0, 0]) ax2 = fig.add_subplot(gs[0, 1])
... create other panels ...
Add panel labels
for i, ax in enumerate([ax1, ax2, ...]): ax.text(-0.15, 1.05, ascii_uppercase[i], transform=ax.transAxes, fontsize=10, fontweight='bold', va='top')
Common Tasks Task 1: Create a Publication-Ready Line Plot
See references/matplotlib_examples.md Example 1 for complete code.
Key steps:
Apply publication style Set appropriate figure size for target journal Use colorblind-friendly colors Add error bars with correct representation (SEM, SD, or CI) Label axes with units Remove unnecessary spines Save in vector format
Using seaborn for automatic confidence intervals:
import seaborn as sns fig, ax = plt.subplots(figsize=(5, 3)) sns.lineplot(data=timeseries, x='time', y='measurement', hue='treatment', errorbar=('ci', 95), markers=True, ax=ax) ax.set_xlabel('Time (hours)') ax.set_ylabel('Measurement (AU)') sns.despine()
Task 2: Create a Multi-Panel Figure
See references/matplotlib_examples.md Example 2 for complete code.
Key steps:
Use GridSpec for flexible layout Ensure consistent styling across panels Add bold panel labels (A, B, C, etc.) Align related panels Verify all text is readable at final size Task 3: Create a Heatmap with Proper Colormap
See references/matplotlib_examples.md Example 4 for complete code.
Key steps:
Use perceptually uniform colormap (viridis, plasma, cividis) Include labeled colorbar For diverging data, use colorblind-safe diverging map (RdBu_r, PuOr) Set appropriate center value for diverging maps Test appearance in grayscale
Using seaborn for correlation matrices:
import seaborn as sns fig, ax = plt.subplots(figsize=(5, 4)) corr = df.corr() mask = np.triu(np.ones_like(corr, dtype=bool)) sns.heatmap(corr, mask=mask, annot=True, fmt='.2f', cmap='RdBu_r', center=0, square=True, linewidths=1, cbar_kws={'shrink': 0.8}, ax=ax)
Task 4: Prepare Figure for Specific Journal
Workflow:
Check journal requirements: references/journal_requirements.md Configure matplotlib for journal: from style_presets import configure_for_journal configure_for_journal('nature', figure_width='single')
Create figure (will auto-size correctly) Export with journal specifications: from figure_export import save_for_journal save_for_journal(fig, 'figure1', journal='nature', figure_type='line_art')
Task 5: Fix an Existing Figure to Meet Publication Standards
Checklist approach (full checklist in references/publication_guidelines.md):
Check resolution: Verify DPI meets journal requirements Check file format: Use vector for plots, TIFF/PNG for images Check colors: Ensure colorblind-friendly Check fonts: Minimum 6-7 pt at final size, sans-serif Check labels: All axes labeled with units Check size: Matches journal column width Test grayscale: Figure interpretable without color Remove chart junk: No unnecessary grids, 3D effects, shadows Task 6: Create Colorblind-Friendly Visualizations
Strategy:
Use approved palettes from assets/color_palettes.py Add redundant encoding (line styles, markers, patterns) Test with colorblind simulator Ensure grayscale compatibility
Example:
from color_palettes import apply_palette import matplotlib.pyplot as plt
apply_palette('okabe_ito')
Add redundant encoding beyond color
line_styles = ['-', '--', '-.', ':'] markers = ['o', 's', '^', 'v']
for i, (data, label) in enumerate(datasets): plt.plot(x, data, linestyle=line_styles[i % 4], marker=markers[i % 4], label=label)
Statistical Rigor
Always include:
Error bars (SD, SEM, or CI - specify which in caption) Sample size (n) in figure or caption Statistical significance markers (, , **) Individual data points when possible (not just summary statistics)
Example with statistics:
Show individual points with summary statistics
ax.scatter(x_jittered, individual_points, alpha=0.4, s=8) ax.errorbar(x, means, yerr=sems, fmt='o', capsize=3)
Mark significance
ax.text(1.5, max_y * 1.1, '***', ha='center', fontsize=8)
Working with Different Plotting Libraries Matplotlib Most control over publication details Best for complex multi-panel figures Use provided style files for consistent formatting See references/matplotlib_examples.md for extensive examples Seaborn
Seaborn provides a high-level, dataset-oriented interface for statistical graphics, built on matplotlib. It excels at creating publication-quality statistical visualizations with minimal code while maintaining full compatibility with matplotlib customization.
Key advantages for scientific visualization:
Automatic statistical estimation and confidence intervals Built-in support for multi-panel figures (faceting) Colorblind-friendly palettes by default Dataset-oriented API using pandas DataFrames Semantic mapping of variables to visual properties Quick Start with Publication Style
Always apply matplotlib publication styles first, then configure seaborn:
import seaborn as sns import matplotlib.pyplot as plt from style_presets import apply_publication_style
Apply publication style
apply_publication_style('default')
Configure seaborn for publication
sns.set_theme(style='ticks', context='paper', font_scale=1.1) sns.set_palette('colorblind') # Use colorblind-safe palette
Create figure
fig, ax = plt.subplots(figsize=(3.5, 2.5)) sns.scatterplot(data=df, x='time', y='response', hue='treatment', style='condition', ax=ax) sns.despine() # Remove top and right spines
Common Plot Types for Publications
Statistical comparisons:
Box plot with individual points for transparency
fig, ax = plt.subplots(figsize=(3.5, 3)) sns.boxplot(data=df, x='treatment', y='response', order=['Control', 'Low', 'High'], palette='Set2', ax=ax) sns.stripplot(data=df, x='treatment', y='response', order=['Control', 'Low', 'High'], color='black', alpha=0.3, size=3, ax=ax) ax.set_ylabel('Response (μM)') sns.despine()
Distribution analysis:
Violin plot with split comparison
fig, ax = plt.subplots(figsize=(4, 3)) sns.violinplot(data=df, x='timepoint', y='expression', hue='treatment', split=True, inner='quartile', ax=ax) ax.set_ylabel('Gene Expression (AU)') sns.despine()
Correlation matrices:
Heatmap with proper colormap and annotations
fig, ax = plt.subplots(figsize=(5, 4)) corr = df.corr() mask = np.triu(np.ones_like(corr, dtype=bool)) # Show only lower triangle sns.heatmap(corr, mask=mask, annot=True, fmt='.2f', cmap='RdBu_r', center=0, square=True, linewidths=1, cbar_kws={'shrink': 0.8}, ax=ax) plt.tight_layout()
Time series with confidence bands:
Line plot with automatic CI calculation
fig, ax = plt.subplots(figsize=(5, 3)) sns.lineplot(data=timeseries, x='time', y='measurement', hue='treatment', style='replicate', errorbar=('ci', 95), markers=True, dashes=False, ax=ax) ax.set_xlabel('Time (hours)') ax.set_ylabel('Measurement (AU)') sns.despine()
Multi-Panel Figures with Seaborn
Using FacetGrid for automatic faceting:
Create faceted plot
g = sns.relplot(data=df, x='dose', y='response', hue='treatment', col='cell_line', row='timepoint', kind='line', height=2.5, aspect=1.2, errorbar=('ci', 95), markers=True) g.set_axis_labels('Dose (μM)', 'Response (AU)') g.set_titles('{row_name} | {col_name}') sns.despine()
Save with correct DPI
from figure_export import save_publication_figure save_publication_figure(g.figure, 'figure_facets', formats=['pdf', 'png'], dpi=300)
Combining seaborn with matplotlib subplots:
Create custom multi-panel layout
fig, axes = plt.subplots(2, 2, figsize=(7, 6))
Panel A: Scatter with regression
sns.regplot(data=df, x='predictor', y='response', ax=axes[0, 0]) axes[0, 0].text(-0.15, 1.05, 'A', transform=axes[0, 0].transAxes, fontsize=10, fontweight='bold')
Panel B: Distribution comparison
sns.violinplot(data=df, x='group', y='value', ax=axes[0, 1]) axes[0, 1].text(-0.15, 1.05, 'B', transform=axes[0, 1].transAxes, fontsize=10, fontweight='bold')
Panel C: Heatmap
sns.heatmap(correlation_data, cmap='viridis', ax=axes[1, 0]) axes[1, 0].text(-0.15, 1.05, 'C', transform=axes[1, 0].transAxes, fontsize=10, fontweight='bold')
Panel D: Time series
sns.lineplot(data=timeseries, x='time', y='signal', hue='condition', ax=axes[1, 1]) axes[1, 1].text(-0.15, 1.05, 'D', transform=axes[1, 1].transAxes, fontsize=10, fontweight='bold')
plt.tight_layout() sns.despine()
Color Palettes for Publications
Seaborn includes several colorblind-safe palettes:
Use built-in colorblind palette (recommended)
sns.set_palette('colorblind')
Or specify custom colorblind-safe colors (Okabe-Ito)
okabe_ito = ['#E69F00', '#56B4E9', '#009E73', '#F0E442', '#0072B2', '#D55E00', '#CC79A7', '#000000'] sns.set_palette(okabe_ito)
For heatmaps and continuous data
sns.heatmap(data, cmap='viridis') # Perceptually uniform sns.heatmap(corr, cmap='RdBu_r', center=0) # Diverging, centered
Choosing Between Axes-Level and Figure-Level Functions
Axes-level functions (e.g., scatterplot, boxplot, heatmap):
Use when building custom multi-panel layouts Accept ax= parameter for precise placement Better integration with matplotlib subplots More control over figure composition fig, ax = plt.subplots(figsize=(3.5, 2.5)) sns.scatterplot(data=df, x='x', y='y', hue='group', ax=ax)
Figure-level functions (e.g., relplot, catplot, displot):
Use for automatic faceting by categorical variables Create complete figures with consistent styling Great for exploratory analysis Use height and aspect for sizing g = sns.relplot(data=df, x='x', y='y', col='category', kind='scatter')
Statistical Rigor with Seaborn
Seaborn automatically computes and displays uncertainty:
Line plot: shows mean ± 95% CI by default
sns.lineplot(data=df, x='time', y='value', hue='treatment', errorbar=('ci', 95)) # Can change to 'sd', 'se', etc.
Bar plot: shows mean with bootstrapped CI
sns.barplot(data=df, x='treatment', y='response', errorbar=('ci', 95), capsize=0.1)
Always specify error type in figure caption:
"Error bars represent 95% confidence intervals"
Best Practices for Publication-Ready Seaborn Figures
Always set publication theme first:
sns.set_theme(style='ticks', context='paper', font_scale=1.1)
Use colorblind-safe palettes:
sns.set_palette('colorblind')
Remove unnecessary elements:
sns.despine() # Remove top and right spines
Control figure size appropriately:
Axes-level: use matplotlib figsize
fig, ax = plt.subplots(figsize=(3.5, 2.5))
Figure-level: use height and aspect
g = sns.relplot(..., height=3, aspect=1.2)
Show individual data points when possible:
sns.boxplot(...) # Summary statistics sns.stripplot(..., alpha=0.3) # Individual points
Include proper labels with units:
ax.set_xlabel('Time (hours)') ax.set_ylabel('Expression (AU)')
Export at correct resolution:
from figure_export import save_publication_figure save_publication_figure(fig, 'figure_name', formats=['pdf', 'png'], dpi=300)
Advanced Seaborn Techniques
Pairwise relationships for exploratory analysis:
Quick overview of all relationships
g = sns.pairplot(data=df, hue='condition', vars=['gene1', 'gene2', 'gene3'], corner=True, diag_kind='kde', height=2)
Hierarchical clustering heatmap:
Cluster samples and features
g = sns.clustermap(expression_data, method='ward', metric='euclidean', z_score=0, cmap='RdBu_r', center=0, figsize=(10, 8), row_colors=condition_colors, cbar_kws={'label': 'Z-score'})
Joint distributions with marginals:
Bivariate distribution with context
g = sns.jointplot(data=df, x='gene1', y='gene2', hue='treatment', kind='scatter', height=6, ratio=4, marginal_kws={'kde': True})
Common Seaborn Issues and Solutions
Issue: Legend outside plot area
g = sns.relplot(...) g._legend.set_bbox_to_anchor((0.9, 0.5))
Issue: Overlapping labels
plt.xticks(rotation=45, ha='right') plt.tight_layout()
Issue: Text too small at final size
sns.set_context('paper', font_scale=1.2) # Increase if needed
Additional Resources
For more detailed seaborn information, see:
scientific-packages/seaborn/SKILL.md - Comprehensive seaborn documentation scientific-packages/seaborn/references/examples.md - Practical use cases scientific-packages/seaborn/references/function_reference.md - Complete API reference scientific-packages/seaborn/references/objects_interface.md - Modern declarative API Plotly Interactive figures for exploration Export static images for publication Configure for publication quality: fig.update_layout( font=dict(family='Arial, sans-serif', size=10), plot_bgcolor='white', # ... see matplotlib_examples.md Example 8 ) fig.write_image('figure.png', scale=3) # scale=3 gives ~300 DPI
Resources References Directory
Load these as needed for detailed information:
publication_guidelines.md: Comprehensive best practices
Resolution and file format requirements Typography guidelines Layout and composition rules Statistical rigor requirements Complete publication checklist
color_palettes.md: Color usage guide
Colorblind-friendly palette specifications with RGB values Sequential and diverging colormap recommendations Testing procedures for accessibility Domain-specific palettes (genomics, microscopy)
journal_requirements.md: Journal-specific specifications
Technical requirements by publisher File format and DPI specifications Figure dimension requirements Quick reference table
matplotlib_examples.md: Practical code examples
10 complete working examples Line plots, bar plots, heatmaps, multi-panel figures Journal-specific figure examples Tips for each library (matplotlib, seaborn, plotly) Scripts Directory
Use these helper scripts for automation:
figure_export.py: Export utilities
save_publication_figure(): Save in multiple formats with correct DPI save_for_journal(): Use journal-specific requirements automatically check_figure_size(): Verify dimensions meet journal specs Run directly: python scripts/figure_export.py for examples
style_presets.py: Pre-configured styles
apply_publication_style(): Apply preset styles (default, nature, science, cell) set_color_palette(): Quick palette switching configure_for_journal(): One-command journal configuration Run directly: python scripts/style_presets.py to see examples Assets Directory
Use these files in figures:
color_palettes.py: Importable color definitions
All recommended palettes as Python constants apply_palette() helper function Can be imported directly into notebooks/scripts
Matplotlib style files: Use with plt.style.use()
publication.mplstyle: General publication quality nature.mplstyle: Nature journal specifications presentation.mplstyle: Larger fonts for posters/slides Workflow Summary
Recommended workflow for creating publication figures:
Plan: Determine target journal, figure type, and content Configure: Apply appropriate style for journal from style_presets import configure_for_journal configure_for_journal('nature', 'single')
Create: Build figure with proper labels, colors, statistics Verify: Check size, fonts, colors, accessibility from figure_export import check_figure_size check_figure_size(fig, journal='nature')
Export: Save in required formats from figure_export import save_for_journal save_for_journal(fig, 'figure1', 'nature', 'combination')
Review: View at final size in manuscript context Common Pitfalls to Avoid Font too small: Text unreadable when printed at final size JPEG format: Never use JPEG for graphs/plots (creates artifacts) Red-green colors: ~8% of males cannot distinguish Low resolution: Pixelated figures in publication Missing units: Always label axes with units 3D effects: Distorts perception, avoid completely Chart junk: Remove unnecessary gridlines, decorations Truncated axes: Start bar charts at zero unless scientifically justified Inconsistent styling: Different fonts/colors across figures in same manuscript No error bars: Always show uncertainty Final Checklist
Before submitting figures, verify:
Resolution meets journal requirements (300+ DPI) File format is correct (vector for plots, TIFF for images) Figure size matches journal specifications All text readable at final size (≥6 pt) Colors are colorblind-friendly Figure works in grayscale All axes labeled with units Error bars present with definition in caption Panel labels present and consistent No chart junk or 3D effects Fonts consistent across all figures Statistical significance clearly marked Legend is clear and complete
Use this skill to ensure scientific figures meet the highest publication standards while remaining accessible to all readers.