From: Eric Durant <edurant@engin.umich.edu>
Subject: Bug in "for": complex not stripped from index type
Date: 26 Mar 2000 00:00:00 GMT
Message-ID: <38DE9776.E7874A3E@engin.umich.edu>
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There seems to be a bug in `for` in Matlab when the index variable
contains a complex value prior to the loop.  The following code
demonstrates this behavior:

=================
j = sqrt(-1);
for j = 1:3,
    j
end
=================

The third line causes the values  1 + 1i,  2 + 1i and  3 + 1i to be
output instead of the expected values 1, 2 and 3.

This is inconsistent with the Matlab documentation, which states
that the values in the expression to the right of the `=` are stored
in the loop variable (no mention is made of handling overwriting a
complex double with a non-complex double as a special case).

I've observed this behavior in the following versions of Matlab:
MATLAB Version 5.3.1.29215a (R11.1) on PCWIN
MATLAB Version 5.3.1.29215a (R11.1) on HP700
MATLAB Version 5.3.1.29215a (R11.1) on SOL2

I'm reporting this to The MathWorks, but thought readers of this
group might be interested as well.

-- Eric Durant
   http://www.edurant.com/