Release calc version 2.10.2t30

help/tanh

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+NAME
+    tanh - hyperbolic tangent
+
+SYNOPSIS
+    tanh(x [,eps])
+
+TYPES
+    x		real
+    eps		nonzero real, defaults to epsilon()
+
+    return	real
+
+DESCRIPTION
+    Calculate the tanh of x to the nearest or next to nearest multiple of
+    epsilon, with absolute error less than .75 * abs(eps).
+
+    tanh(x) = (exp(2*x) - 1)/(exp(2*x) + 1)
+
+EXAMPLE
+    > print tanh(1, 1e-5), tanh(1, 1e-10), tanh(1, 1e-15), tanh(1, 1e-20)
+    .76159 .761594156 .761594155955765 .76159415595576488812
+
+LIMITS
+    unlike sin and cos, x must be real
+    eps > 0
+
+LIBRARY
+    NUMBER *qtanh(NUMBER *x, NUMBER *eps)
+
+SEE ALSO
+    sinh, cosh, sech, csch, coth, epsilon