Series with complex coefficients and real powers for PHCv2.4.91

An exponential series is a sequence of two vectors:
(1) nonzero complex coefficients for the terms in the series; and
(2) corresponding real exponents sorted in increasing order.

Run "gprbuild exponentials.gpr" to make all test programs.
On windows, type "gprbuild exponentials.gpr -Xos=windows"
at the PowerShell prompt.
The "gprclean exponentials.gpr" removes all files created by gprbuild.

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file name                          : short description
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double_exponential_arithmetic      : arithmetic on exponential series
test_double_exponentials           : test operations on exponentials
ts_expops                          : tests arithmetical operations
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