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cdf - Cumulative distribution functions

Syntax

Y = cdf(name,X,A)
Y = cdf(name,X,A,B)
Y = cdf(name,X,A,B,C)

Description

Y = cdf(name,X,A) computes the cumulative distribution function for the one-parameter family of distributions specified by name. A contains parameter values for the distribution. The cumulative distribution function is evaluated at the values in X and its values are returned in Y.

If X and A are arrays, they must be the same size. If X is a scalar, it is expanded to a constant matrix the same size as A. If A is a scalar, it is expanded to a constant matrix the same size as X.

Y is the common size of X and A after any necessary scalar expansion.

Y = cdf(name,X,A,B) computes the cumulative distribution function for two-parameter families of distributions, where parameter values are given in A and B.

If X, A, and B are arrays, they must be the same size. If X is a scalar, it is expanded to a constant matrix the same size as A and B. If either A or B are scalars, they are expanded to constant matrices the same size as X.

Y is the common size of X, A, and B after any necessary scalar expansion.

Y = cdf(name,X,A,B,C) computes the cumulative distribution function for three-parameter families of distributions, where parameter values are given in A, B, and C.

If X, A, B, and C are arrays, they must be the same size. If X is a scalar, it is expanded to a constant matrix the same size as A, B, and C. If any of A, B or C are scalars, they are expanded to constant matrices the same size as X.

Y is the common size of X, A, B, and C after any necessary scalar expansion.

Acceptable strings for name are:

Examples

Compute the cdf of the normal distribution with mean 0 and standard deviation 1 at inputs –2, –1, 0, 1, 2:

p1 = cdf('Normal',-2:2,0,1)
p1 =
  0.0228  0.1587  0.5000  0.8413  0.9772

The order of the parameters is the same as for normcdf.

Compute the cdfs of Poisson distributions with rate parameters 0, 1, ..., 4 at inputs 1, 2, ..., 5, respectively:

p2 = cdf('Poisson',0:4,1:5)
p2 =
  0.3679  0.4060  0.4232  0.4335  0.4405

The order of the parameters is the same as for poisscdf.

See Also

pdf, icdf

  


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