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Options

Every control on the Sampling Matrix dialog. There are four settings and two buttons, and nothing is stored: the dialog opens with the same defaults every time.

Sampling method

Three choices, and the one you pick decides both how the coded values are produced and which limits apply to the two counts below it.

Descriptive Sampling

Latin Hypercube Sampling

Sobol Sampling

Choosing Sobol Sampling changes the dialog: the number of rows becomes a list instead of a typing box, the row limits become 16 to 32,768, and the factor limit rises to 1,000.

Number of factors

How many columns the matrix has, which is one per factor.

Method	Range
Descriptive Sampling, Latin Hypercube Sampling	1 to 250
Sobol Sampling	1 to 1,000

The hint under the box states the range that applies to the method currently selected.

Number of rows

How many runs the matrix has, which is one per row.

For Descriptive Sampling and Latin Hypercube Sampling this is a typing box accepting 2 to 20,000.

For Sobol Sampling it is a list, and the hint reads A power of two, 16 to 32,768. It is a list rather than a box because no other number can be right for this method, so the dialog offers only the numbers that are. Switching to Sobol lands the list on the smallest offered value at or above whatever was typed before. That choice is on screen before anything is built, so the matrix is never built from a number you did not see.

Seed

The number the sampling starts from. The same seed builds the same matrix.

Any whole number from 0 to 4,294,967,295 is accepted, 0 included, and it is used exactly as given.

Create Matrix and Cancel

Create Matrix builds the matrix and writes the new worksheet. Cancel closes the dialog and writes nothing.

Create Matrix is never greyed out. Pressing it while a number is wrong shows the problem and puts the cursor in the box that is wrong, rather than leaving a disabled button with no explanation.

When a number is refused

One problem is shown at a time, introduced by the word Problem:, and it names the limit that was broken so you are told what to type. A number outside its limits is refused and never quietly changed to a legal one.

The messages, as the dialog words them:

Situation	Message
Rows outside the general range	The number of rows must be between 2 and 20,000.
Rows outside the Sobol range	Sobol needs a number of rows between 16 and 32,768.
Rows inside the Sobol range but not a power of two	Sobol needs a number of rows that is a power of two.
Factors outside the general range	The number of factors must be between 1 and 250.
Factors outside the Sobol range	The number of factors must be between 1 and 1,000.
Seed not a whole number in range	The seed must be a whole number between 0 and 4,294,967,295.