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implementing Python 2.7 and matplotlib when saving figures with custom DPI settings

👀 Views: 79 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-16
python-2.7 matplotlib dpi Python

I've been banging my head against this for hours... I'm experiencing unexpected behavior when trying to save figures using matplotlib in Python 2.7. Specifically, when I set a custom DPI value, the output image appears to be much larger than expected, even when I specify a reasonable figure size. For example, I'm using the following code: ```python import matplotlib.pyplot as plt # Create a simple plot plt.figure(figsize=(5, 5)) plt.plot([1, 2, 3], [4, 5, 6]) plt.title('My Plot') # Save the figure with a custom DPI plt.savefig('my_plot.png', dpi=300) ``` After running this, the produced 'my_plot.png' file is significantly larger than a 5x5 inch figure would normally be at 300 DPI. When I open the image, it appears to be over 1500x1500 pixels, leading me to believe there's an scenario with how the `figsize` and `dpi` parameters are interacting. I've tried adjusting the `figsize` to both smaller and larger values, but the output continues to scale incorrectly. Additionally, I've ensured that my matplotlib version is 1.5.1, which is compatible with Python 2.7. I also checked that other file formats, such as SVG, exhibit the same scaling scenario when saving. Is there a known scenario with matplotlib in Python 2.7 regarding DPI settings? What steps can I take to ensure that the saved image matches the intended size according to the DPI setting? For context: I'm using Python on Linux. Any ideas what could be causing this? My development environment is macOS. What am I doing wrong? This is happening in both development and production on Ubuntu 22.04. Has anyone else encountered this?