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  "page": "https://www.calculatorx.com/calc/math/ln",
  "api": "https://www.calculatorx.com/api/v1/calc/ln",
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  "assumptions": [
    "Real arithmetic; argument x > 0. Base is e, not 10.",
    "On many calculators log means log₁₀; in some programming languages log(x) means ln(x).",
    "Published engine is y = ln(x). A legacy y query parameter is ignored and stripped from the address bar. Inverse x = e^y is Antilog with base e."
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    "x ≤ 0 returns INVALID_ARGUMENT (real ln is undefined).",
    "x = 1 returns 0 (exact). The token e and the binary64 constant Math.E return 1 with the exact display flag; Math.E is a rounded approximation of the mathematical constant e, not an exact representation.",
    "0 < x < 1 yields a negative result (for example ln(0.5) = −ln(2)).",
    "For every finite x > 0 in binary64, y = ln(x) is finite (about −744 < y < 710). Domain errors use INVALID_ARGUMENT; the engine does not return Infinity for valid positive finite inputs."
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      "supports": "Natural logarithm as the inverse of the exponential; ln(x)=y ⇔ e^y=x",
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      "supports": "e^(ln x) = x and ln(e^y) = y for real x > 0",
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      "publisher": "National Institute of Standards and Technology"
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      "section": "Natural logarithm base e; real argument x > 0",
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