16 KiB
Scientific Visualization
Overview
This skill provides comprehensive guidance, tools, and best practices for creating publication-ready scientific figures. It covers proper figure composition, colorblind-friendly design, journal-specific requirements, and practical implementation using matplotlib, seaborn, and plotly.
Publication-ready figures must be:
- Clear: Immediately understandable with proper labeling
- Accurate: Truthful data representation without distortion
- Accessible: Interpretable by readers with color vision deficiencies
- Professional: Polished appearance meeting journal standards
When to Use This Skill
Activate this skill 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 ...
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')
2. 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,BrBGinstead) - Never use
jetorrainbowcolormaps
Always test figures in grayscale to ensure interpretability.
3. 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
4. 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')
5. 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
Task 2: Create a Multi-Panel Figure
See references/matplotlib_examples.md Example 2 for complete code.
Key steps:
- Use
GridSpecfor 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
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.mdfor extensive examples
Seaborn
- Built on matplotlib, inherits all matplotlib customizations
- Good for statistical plots
- Apply matplotlib styles first, then use seaborn
import seaborn as sns
from style_presets import apply_publication_style
apply_publication_style('default')
sns.set_palette(['#E69F00', '#56B4E9', '#009E73']) # Okabe-Ito colors
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 utilitiessave_publication_figure(): Save in multiple formats with correct DPIsave_for_journal(): Use journal-specific requirements automaticallycheck_figure_size(): Verify dimensions meet journal specs- Run directly:
python scripts/figure_export.pyfor examples
-
style_presets.py: Pre-configured stylesapply_publication_style(): Apply preset styles (default, nature, science, cell)set_color_palette(): Quick palette switchingconfigure_for_journal(): One-command journal configuration- Run directly:
python scripts/style_presets.pyto 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 qualitynature.mplstyle: Nature journal specificationspresentation.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.