NEC-LIST: Basis functions on short segments.

Good day Jerry,

I have been studying the basis-function coefficients for a
basis function defined over 3 segments, each of length d.
For k=wave number, kd<<1, I find C=1+(3/8)(kd)^2 in both
NEC2 and NEC4. In the case of NEC2, the mid-segment value
of the basis function is (3/8)(kd)^2. This implies that the
fields due to a constant current and those due to the cosine
current will mostly cancel. I assumed this is the cause of
the potential loss of precision in NEC2 mentioned in NEC4.
    When I evaluate the coefficients in NEC4 for the same
conditions, I find the same C, and A=(3/8)(kd)^2. Because
of the function definiton change, only A is the mid-segment
value for the central component function. Indeed, the
multipliers of the field values for a contant current and a
cosine current are the same as they are in NEC2.
    Please enlighten me on the precision loss issue.

Thanks,
Doug Miron

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