exprnd

Pseudo-random number of an exponential distribution

Usages

exprnd(mu)

• It returns pseudo-random numbers of exponential distributions with mean values given by mu.
• mu should contains positive real numbers.
• The output has the same size as mu.

exprnd(mu,m)

• It returns pseudo-random numbers of exponential distributions with means given by mu.
• m should be a positive integer.
• The output is an m-by-m matrix.
• mu should be a scalar or an m-by-m matrix.
• mu should contains positive real numbers.

exprnd(mu, s1, s2, ..., sn)

• It returns pseudo-random numbers of exponential distributions with means given by mu.
• s1, s2, ... sn should be non-negative real integers.
• The output has the size [s1, s2, ..., sn].
• mu should be a scalar or an array of size [s1, s2, ..., sn].
• mu should contains positive real numbers.

exprnd(mu, sizeVec)

• It returns an array of pseudo-random numbers which follow exponential distributions with means given by mu. The output's size is specified by the size vector sizeVec.
• mu should be a scalar, or an array of size sizeVec.
• mu should contains positive real numbers.

Examples

• This example models the times between independent arrivals of a queue using exponential distribution. If there are on average 3 customer arrivals per minute, then the mean inter-arrival time is $1/3$. Hence, $1/3$ is the mean of the exponential distribution.

Input

% Random inter-arrival times of a queue 
% with mean customer-arrival rate 
% equal to 3 people per minute.

% Mean inter-arrival time (minutes per customer)
mean_time = 1 / 3;
% 10 random interval-arrival times
r = exprnd(mean_time, 1, 10)

Output

r = 1e-1 × 
Columns 1 through 3:
 3.5380   0.3408   3.1718
Columns 4 through 6:
 8.4215   7.0371   0.3357
Columns 7 through 9:
 0.0515   0.7422   3.0326
Column 10:
 1.2894

Differences With MATLAB

• Since this app's algorithms for generating random numbers and initial states may be different from MATLAB's, users should not expect this app and MATLAB to give the same sequences of pseudo-random numbers.