1ERF(3M) ERF(3M)
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6 erf, erfc - error functions
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9 #include <math.h>
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11 double erf(x)
12 double x;
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14 double erfc(x)
15 double x;
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18 Erf(x) returns the error function of x; where
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20 erf(x) = 2/sqrt(pi)∗integral from 0 to x of exp(-t∗t) dt.
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22 Erfc(x) returns 1.0-erf(x).
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24 The entry for erfc is provided because of the extreme loss of relative
25 accuracy if erf(x) is called for large x and the result subtracted from
26 1. (e.g. for x = 10, 12 places are lost).
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29 math(3M)
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334.3 Berkeley Distribution May 12, 1986 ERF(3M)