If you specify a CONTROL statement, PROC SURVEYSELECT sorts the input data set by the CONTROL variables before selecting the sample. If you also specify a STRATA statement, the procedure sorts by ...

In programming, a variable that keeps track of the number of iterations of a process. Its value is incremented or decremented with each iteration, and it is compared to a constant or other variable to ...

Variable names are alphanumeric but must start with a letter. The length of a variable name is limited to thirty-two characters for non-SAS data set variables Model variables are declared by VAR, ...

This application note describes a closed loop, computer- controlled, variable attenuator for the control of output power from a tunable laser. It is based on the combination of a 1/2 wave-plate and a ...

Fixed expenses are easier to plan around because they stay the same from one month to the next. Variable expenses, on the other hand, are less predictable. Understanding both types and how they impact ...

Why get up close and personal with a resistor when you can tweak it from a distance? Remote variable resistors make analog circuit control easier, neater, and a lot more fun. Well, we are about to ...

In this article, as in industry, advanced process control (APC) refers primarily to multi-variable control. Multivariable control means adjusting multiple single-loop controllers in unison, to meet ...

Just over a decade ago, an article titled, "Advanced Control Strategies Move into the Field" (Control, October 2008), highlighted three evolving trends in the process control world that would "make ...