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Xnumbers Tutorial
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• xstdevp returns the population standard deviation
n
x x
p
∑
−
=
2
)
(
σ
Variance
xvar(range, [Digit_Max])
xvarp(range, [Digit_Max])
Return the variance of n numbers, extended or not. Range is a range of cells. The optional
parameter Digit_Max, from 1 to 200, sets the number of significant digits (default 30)
• xvar returns the standard variance
1
)
(
2
−
−
=
∑
n
x x
v
• xvarp returns the population variance
n
x x
v
p
∑
−
=
2
)
(
Probability distributions
Xnumbers contains several type of probability distribution functions
DSBeta(x, a, b, [dtype])
Beta distribution
0 < x < 1 , a > 0, b > 0,
DSBinomial(k, n, p, [dtype])
Binomial distribution
k integer, n integer , 0 < p < 1
DSCauchy(x, m, s, n, [dtype])
Cauchy (generalized) distribution
n integer , s > 0
DSChi(x, r, [dtype])
Chi distribution
r integer, x > 0
DSErlang(x, k, l, [dtype]))
Erlang distribution
k integer, x > 0
DSGamma(x, k, l, [dtype]))
Gamma distribution
x > 0, k > 0, l > 0
DSLevy(x, l, [dtype]))
Levy distribution
x > 0, l > 0
DSLogNormal(x, m, s, [dtype]))
Log-normal distribution
x > 0, m ≥ 0, s > 0
DSLogistic(x, m, s, [dtype]))
Logistic distribution
x > 0, m ≥ 0, s > 0
DSMaxwell(x, a, [dtype]))
Maxwell-Boltzman distribution
x > 0, a > 0
DSMises(x, k, [dtype]))
Von Mises distribution
k > 0, -π < x < π
DSNormal(x, m, s, [dtype]))
Normal distribution
s > 0
DSPoisson(k, z, [dtype]))
Poisson distribution
k integer, z > 0
DSRayleigh(x, s, [dtype]))
Rayleigh distribution
x > 0, s > 0
DSRice(x, v, s, [dtype]))
Rice distribution (j=1 cumulative)
x > 0, v ≥ 0 , s > 0
DSStudent(t, v, [dtype]))
Student distribution (j=1 cumulative)
v integer degree of freedom
DSWeibull(x, k, l, [dtype]))
Weibull distribution (j=1 cumulative)
x > 0, k integer, l > 0
The optional parameter dtype = 0 (default) returns the density distribution f(x); dtype = 1
returns the cumulative distribution F(x).
(
)
∫
=
<
=
x
a
f tdt
x
P
F x
()
( )
x
The lower limit "a" depends by the definition domain of the density function f(x).
