These functions calculate the complex square root of
z,
with a branch cut along the negative real axis.
(That means that csqrt(-1+eps*I) will be close to I while
csqrt(-1-eps*I) will be close to -I, if eps is a small positive
real number.)
VERSIONS
These functions were added in glibc 2.1.
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).