`log_a x < log_b x` is the mathematically correct result. Due to inherent rounding from floats being a finite representation of real numbers, `log_a x <= log_b x` would be expected from any correct implementation using floats. So either `true true false` or `true false true` would be reasonable. (I made a mistake in the previous comment, LuaJIT returns `<` for me, just like in your comment, not `=`.)
The topic of the post is that in PHP and Lua (without LuaJIT), sometimes this inequality doesn't hold, and instead we get `log_a x > log_b x`, which is very incorrect and cannot be explained away by rounding.
The topic of the post is that in PHP and Lua (without LuaJIT), sometimes this inequality doesn't hold, and instead we get `log_a x > log_b x`, which is very incorrect and cannot be explained away by rounding.
Does that make more sense?