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The compose Command

The compose command is used to create vectors. It has two forms:

compose vecname param = value [...]
or

compose vecname values value [...]
Both forms of this command create a new vector called vecname. In the first form, the values in the vector are determined by the parameters given, as described below. In the second form, indicated by the keyword ``values'', the given values are used to form the vector.

In the first form, there are three groups of possible parameter sets. The first set facilitates creation of uniform arrays. This set contains the following parameters.

start The value at which the vector should start
stop The value at which the vector should end
step The difference between successive elements
lin The number of points, linearly spaced
log The number of points, logarithmically spaced
dec The number of points per decade, logarithmically spaced

The words ``len'' and ``length'' are synonyms for ``lin''. A subset of these parameters that provides the information needed is sufficient. If all four are given, the point count and step value must be consistent or the command will fail. The parameter start defaults to zero, unless implicitly set by other parameters. The stop and step have no defaults and must be supplied unless implied by other parameters. If the lin parameter is not given, the other parameters determine the vector length.

The second parameter group generates Gaussian random values.

gauss The number of points in the gaussian distribution
mean The mean value for the gaussian distribution
sd The standard deviation for the gaussian distribution

The gauss parameter is required, sd defaults to 1.0, and mean defaults to 0. The random number sequences can be reset by calling the seed command.

The third parameter group generates uniform random values.

random The number of randomly selected points
center Where to center the range of points
span The size of the range of points

The random parameter is required, span defaults to 2.0, and center defaults to 0. The random number sequences can be reset by calling the seed command.


next up previous contents index
Next: The cross Command Up: Data Manipulation Commands Previous: Data Manipulation Commands   Contents   Index
Stephen R. Whiteley 2017-10-02