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  (c) TransEra Corp, 2021
Ci
Cosine integral.
 
Loading        LOADSUB ALL FROM "EI.HTS"
or LOADSUB FROM "MATHLIB.HTS"
 
Usage                REAL X,Y
Y=FNCi(X)
 
Description                
FNCi returns the value of the cosine integral of x, Ci(x). Ci(x) is defined by the relation
where γ is Euler's number; γ = 0.57721566490153...
 
The real version of Ci(x) is only defined for positive values of x. Large positive values of x may produce results greater than MAXREAL, the largest value representable.
 
Ci(x)
Errors
FNCi causes an HTBasic error if its argument is not of type REAL. It also causes an error if the value of x is negative or zero or if Ci(x) would be greater than MAXREAL.
 
See Also                
Ei, Ci, Shi, Si