> Rarely
have to? For a professional programmer, writing their own binary search for actual use at work is nearly a firing offense (with a
very few exceptions).
You really don't sound like you do much coding. I've lost count of the number of times I've had to write my own binary search simply because the existing ones were painfully inadequate.
Pretty much every standard library implementation, for example, expects the data to be in an array in memory. There's no provision for the data to be dynamically obtained (e.g. from disk or generated on the fly) or in any other form in memory (e.g. unsafe/native int pointers in C#). And have fun running your standard library's binary search, whether Python or C++ or Java or whatever, on something more abstract like the numeric interval [0.5, 1.0]. There's just no way to specify alternate termination conditions like tolerances.
Oh, and this is completely ignoring more mundane shortcomings in a significant fraction of implementations, like how in C# there is (or at least was, last I checked) no way to directly obtain both the lower and upper bounds of an equal range via binary search. At least C++ has equal_range!
I could say the same for practically any classical CS 101 algorithm like depth-first search or Dijkstra or whatever you want, too, except those don't even exist in most standard libraries in the first place... and I suspect their lack of existence is not unrelated to their likely practical inadequacy.
You really don't sound like you do much coding. I've lost count of the number of times I've had to write my own binary search simply because the existing ones were painfully inadequate.
Pretty much every standard library implementation, for example, expects the data to be in an array in memory. There's no provision for the data to be dynamically obtained (e.g. from disk or generated on the fly) or in any other form in memory (e.g. unsafe/native int pointers in C#). And have fun running your standard library's binary search, whether Python or C++ or Java or whatever, on something more abstract like the numeric interval [0.5, 1.0]. There's just no way to specify alternate termination conditions like tolerances.
Oh, and this is completely ignoring more mundane shortcomings in a significant fraction of implementations, like how in C# there is (or at least was, last I checked) no way to directly obtain both the lower and upper bounds of an equal range via binary search. At least C++ has equal_range!
I could say the same for practically any classical CS 101 algorithm like depth-first search or Dijkstra or whatever you want, too, except those don't even exist in most standard libraries in the first place... and I suspect their lack of existence is not unrelated to their likely practical inadequacy.