Does the "unique" function work with 64 bit integers?

Ken
2016 8 24
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I was trying to sort a set of 64 bit integers using the "unique" function. This function seems to convert them to a 64 bit integer before sorting, though.
Example:
x=uint64(2^63)+uint64(0:1024)';
y=unique(x);
The output, y, is a single number, 9223372036854775808, rather than a column of 1025 integers, since the last 11 bits are rounded off.
The "sort" sorts the data properly, but does not remove duplicates. Are there any other solutions? I am using Matlab R2012a.

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James Tursa
James Tursa 2016-8-24

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Maybe use something similar to this as a workaround:
y = x(logical([1;diff(sort(x))]));

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Ken
Ken 2016-8-24
Yes. That works. The hard part was figuring out why my output did not match my input. I see in the UNIQUE function code where it changes the input to double precision. There is a comment in the code that "UNIQUE calls DIFF, which requires double input." This has not been true since R2010b, when the DIFF function began to work with integers. Thanks.

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