HP 40gs User Manual page 167

hp40g+.book Page 13 Friday, December 9, 2005 1:03 AM
PERM
RANDOM
H I N T
UTPC
UTPF
UTPN
Using mathematical functions
Factorial of a positive integer. For non-integers, ! = Γ(x +
1). This calculates the gamma function.
value!
Number of permutations (with regard to order) of n things
taken r at a time: n!/(r!(n-r)!
PERM (n, r)
Example
PERM(5,2) returns 20. That is, there are 20
different permutations of five things taken two at a
time.
Random number (between zero and 1). Produced by a
pseudo-random number sequence. The algorithm used in
the RANDOM function uses a seed number to begin its
sequence. To ensure that two calculators must produce
different results for the RANDOM function, use the
RANDSEED function to seed different starting values
before using RANDOM to produce the numbers.
RANDOM
The setting of Time will be different for each calculator, so
using RANDSEED(Time) is guaranteed to produce a set of
numbers which are as close to random as possible. You
can set the seed using the command RANDSEED.
Upper-Tail Chi-Squared Probability given degrees of
freedom, evaluated at value. Returns the probability that
2
a χ
random variable is greater than value.
UTPC(degrees, value)
Upper-Tail Snedecor's F Probability given numerator
degrees of freedom and denominator degrees of freedom
(of the F distribution), evaluated at value. Returns the
probability that a Snedecor's F random variable is
greater than value.
UTPF(numerator, denominator, value)
Upper-Tail Normal Probability given mean and variance,
evaluated at value. Returns the probability that a normal
random variable is greater than value for a normal
distribution. Note: The variance is the square of the
standard deviation.
UTPN(mean, variance, value)
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