René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Certain unicode in Matplotlib + LaTeX","articleBody":"The following code fails at `set_ylabel`:\r\n\r\n```python\r\nimport matplotlib.pyplot as plt\r\n\r\nwith plt.style.context({'text.usetex': True}):\r\n    (fig, ax) = plt.subplots()\r\n    ax.set_xlabel(\"€\")\r\n    ax.set_ylabel(\"Δ\")\r\n    plt.show()\r\n```\r\n\r\nIt works with `$\\Delta$` instead of Δ and it works if I unset `text.usetex`.\r\n\r\nThe generated tex is this:\r\n\r\n```tex\r\n\\documentclass{article}\r\n\\newcommand{\\mathdefault}[1]{#1}\r\n\\usepackage{type1cm}\r\n\\usepackage{type1ec}\r\n\\usepackage{type1ec}\r\n\\usepackage{type1ec}\r\n\\usepackage[utf8]{inputenc}\r\n\\DeclareUnicodeCharacter{2212}{\\ensuremath{-}}\r\n\\usepackage[papersize=72in, margin=1in]{geometry}\r\n\r\n\\makeatletter\\@ifpackageloaded{textcomp}{}{\\usepackage{textcomp}}\\makeatother\r\n\\pagestyle{empty}\r\n\\begin{document}\r\n% The empty hbox ensures that a page is printed even for empty inputs, except\r\n% when using psfrag which gets confused by it.\r\n\\fontsize{10.000000}{12.500000}%\r\n\\ifdefined\\psfrag\\else\\hbox{}\\fi%\r\n{\\sffamily Δ}\r\n\\end{document}\r\n```\r\n\r\nand it compiles fine with pdflatex if I replace `\\usepackage[utf8]{inputenc}` by `\\usepackage[utf8x]{inputenc}`. Otherwise the error is the same:\r\n\r\n```tex\r\n! Package inputenc Error: Unicode character Δ (U+0394)\r\n(inputenc)                not set up for use with LaTeX.\r\n```\r\n\r\nI think this is on the side of unexpected behavior.\r\n\r\nVersions: `Python 3.8.5` and `matplotlib==3.4.1`.\r\n\r\n","author":{"url":"https://github.com/numpde","@type":"Person","name":"numpde"},"datePublished":"2021-05-19T10:00:39.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/20262/matplotlib/issues/20262"}