HP 40gs hp 40gs_user's guide_English_E_HDPMSG40E07A.pdf - Page 167

hp40g+.book Page 13 Friday, December 9, 2005 1:03 AM PERM RANDOM HINT 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. UTPC UTPF UTPN Upper-Tail Chi-Squared Probability given degrees of freedom, evaluated at value. Returns the probability that a χ2 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) Using mathematical functions 13-13