randerr

Generate bit error patterns

Syntax

out = randerr(m)
out = randerr(m,n)
out = randerr(m,n,errors)
out = randerr(m,n,prob,state)

Description

For all syntaxes, randerr treats each row of out independently.

out = randerr(m) generates an m-by-m binary matrix, each row of which has exactly one nonzero entry in a random position. Each allowable configuration has an equal probability.

out = randerr(m,n) generates an m-by-n binary matrix, each row of which has exactly one nonzero entry in a random position. Each allowable configuration has an equal probability.

out = randerr(m,n,errors) generates an m-by-n binary matrix, where errors determines how many nonzero entries are in each row:

Once randerr determines the number of nonzero entries in a given row, each configuration of that number of nonzero entries has equal probability.

out = randerr(m,n,prob,state) is the same as the syntax above, except that it first resets the state of the uniform random number generator rand to the integer state.

Examples

The examples below generate an 8-by-7 binary matrix, each row of which is equally likely to have either zero or two nonzero entries, and then alter the scenario by making it three times as likely that a row has two nonzero entries. Notice in the latter example that the second row of the error parameter sums to one.

out = randerr(8,7,[0 2])

out2 = randerr(8,7,[0 2; .25 .75])

Sample output is below.

out =

     0     0     0     0     0     0     0
     0     0     0     0     0     0     0
     0     0     1     0     0     0     1
     1     0     1     0     0     0     0
     0     0     0     0     0     0     0
     0     0     0     0     0     0     0
     0     0     0     0     1     1     0
     1     0     1     0     0     0     0


out2 =

     0     0     0     0     0     0     0
     1     0     0     0     0     0     1
     1     0     0     0     0     0     1
     0     0     0     1     0     1     0
     0     0     0     0     0     0     0
     0     1     0     0     0     0     1
     0     0     0     0     0     0     0
     1     0     0     0     1     0     0

See Also

rand, randsrc, randint, Signal Sources


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