alt Hacker NewsIt depends on the field.
For example in programming base e is more common. For example log is base e in C/C++, JavaScript, Java, Python, Perl, Mathematica, Fortran, and Rust.
Another example is number theory. I just checked a few number theory books from my library and most used base e: Hardy & Wright's "An Introduction to the Theory of Numbers", Apostol's "Introduction to Analytic Number Theory", Baker's "A Comprehensive Course in Number Theory", Ingham's "The Distribution of Prime Numbers", Baker's "Transcendental Number Theory", Ribenboim's "The Book of Prime Number Records", Kumanduri & Romero's "Number Theory with Computer Applications", and Niven's "Irrational Numbers".
The only number theory book I found using ln rather than log was Gelfond's "Transcendental & Algebraic Numbers".
That confusion is unfortunate, thanks for checking the books!
Am now a bit curious as to what the country/scientific field table with most common log notation would look like as it seems there is indeed a lot of variance...
https://mathworld.wolfram.com/Ln.html
> The United States Department of Commerce recommends that the notation lnx be used in this way to refer to the natural logarithm (Taylor 1995, p. 33).
> Unfortunately, mathematicians in the United States commonly use the symbol logx to refer to the natural logarithm, as does TraditionalForm typesetting in the Wolfram Language