Control statement

Control statements affect the flow of instructions within a program unit. (For control between units, see subprogram statements later.) These may be general, conditional, or iterative statements. General control statements are ... 

Control statements—Affect the flow of statement execution within a program unit (see subprogram statements below for passing of control between units). The only general control statement in Pascal (which is rarely needed) is ... 

CDC. 1986. Centers for Disease Control statement on breastfeeding. Centers for Disease Control. Vet Hum Toxicol 28 582-583. 

Ultimately, one of the goals in the development of the expert system ACexpert is to incorporate the system into the automated control program of any instrument. This would require that the modules be sufficiently generic that only the control statements, and the specific chemistry encoded as conditions and cases would have to be changed. For this goal to be realized, the knowledge base would have to be created by some form of automated knowledge acquisition module. 

FORTRAN, the most widely used language at that time, used a complicated format control statement for all input or output in the program, a requirement too complicated for most students, particularly for those not taking science or engineering. 

C like most programming languages, is based on a core feature set that is common and uncontroversial. The core features deal with the rules for storing and managing data, and with control statements (control structures) that let a programmer specify a sequence of operations on data. 

C has two additional flow of control statements, break and continue, that augment the capabilities of the loops that have just been described. The break statement is used to break out of (to immediately terminate) the enclosing do, while, for, or switch statement. Its use is routine in switch statements, to terminate the switch statement at the conclusion of each individual case. In do, while, and for loops, break is often used to terminate the loop prematurely when an error or special condition occurs. Using a break in the body of a loop often simplifies the control expression of the loop, because it allows special case code to be placed elsewhere. 

It is also possible to create functions in Mathcad. The authors leave it up to the reader to explore function options more fully but review control structures for functions here, including/or loops, while loops, and /statements. The general format for control statements is as follows ... 

While loops are entered in a similar way to for loops however, while is chosen. The condition statements will continue to be executed so long as the while criteria is met.. Tloops are also from the same toolbar, choosing if. condition statements are executed only if the condition statement is evaluated as the Boolean true. Control statements can be made increasingly complex by adding lines. It is important to remember that the user cannot type while, if or for but must select the operator from the programming toolbox. It is also important to note that Mathcad indexes from zero and a subscript operator (found in the matrix toolbar) must be used to call a specific element. Please see Section 5.3.1 for the implementation of a for loop. 

In the VT, all flow-of-control statements are translated into SELECT nodes. The Workbench maps each branch onto a distinct set of states in the controller and thus is referred to as a control select. Any multiplexors created to steer data values as part of this implementation will have their select lines connected to the state machine. The alternative implementation is a data select. In our data select implementation, the entire control construct is replaced by combinational logic. Any multiplexors required as part of this implementation would have their select lines connected to data values rather than control values. One way of interpreting this transformation is that all branches of the SELECT are precomputed in parallel, and then a multiplexing structure is added at the bottom to select the appropriate output values, depending on the branch condition. 

A MATLAB code, or m-file, is a collection of commands that are executed sequentially. Commands can be mathematical operations, function calls, flow control statements, and calls to the functions and scripts described in Section C.1.4. m-files are written using the MATLAB editor and have names such as my file. m. They are executed from the MATLAB command window by typing the name of the m-file (without the. m). Saving an m-file will avoid many hours of retyping the same commands. 

So let us look at the multiplication operation. First, another type of loop is being used. The Infinite Loop is not always supported by sjoithesizers owing to the unpredictable nature of their operation - the loop could be unrolling forever if a condition that causes an exit is never met. Similarly, the While Loop is often not supported for synthesis. The s)mtax of bodi these alternative loop types is shown in Box 6.11. This loop is controlled by the counter I, which increments on each pass around the loop. When I reaches the n - the number of bits in A - the Exit statement quits the loop. This statement does not necessarily require the loop label in this example but one should be used when embedding loops to darify which loop is to be stopped. Next is another loop control statement that will immediately start the next iteration of the loop, assuming its condition is met. They are both discussed in Box 6.12. 

Program control statements include those for decision making (branching) and for looping. Many such statements available in VBA are discussed below. Ones less frequently used (or ones that are repetitious) are not covered. 

In addition Lua has two types of for control statements. One is a numeric for statement of the form ... 

In the definition phase options are narrowed down and a preferred solution is proposed. The project becomes better defined in terms of what should be built and how it should be operated, and an assessment of how the project may be affected by changes beyond the control of the company (for example the oil price) should be made. Normally a clear statement should be prepared, describing why the option is preferred and what project specifications must be met, to be used as a basis for further work. 

As a consequence of this, i enever bulk dlffusional resistance domin ates Knudsen diffusional resistance, so that 1, it follows that fi 1 also, and hence viscous flow dominates Knudsen streaming. Thus when we physically approach the limit of bulk diffusion control, by increasing the pore sizes or the pressure, we must simultaneously approach the limit of viscous flow. This justifies a statement made in Chapter 5. 

In Program QWIEN (written in QBASIC, Appendix A), x is initialized at 1 and incremented by 0.1 in line 3, which is given the statement number 10 for future reference. Be careful to differentiate between a statement number like 10 x = x -E. 1 and the product 10 times r which is 10%. A number a is calculated for x= 1.1 that is obviously too small so (a — 1) is less than 0 and the IF statement in line 5 sends conhol back to the statement numbered 10, which increments a by 0.1 again. This continues until (a — 1) > 0, whereupon control exits from the loop and prints the result for a and a . 

Quality control encompasses all activities used to bring a system into statistical control. The most important facet of quality control is written documentation, including statements of good laboratory practices, good measurement practices, standard operating procedures, and protocols for a specific purpose. 

Statement on the Eole of Dieta Management in Hypertension Control, National High Blood Pressure Education Program and Coordinating Committee, Bethesda, Md., 1979. 

Fuzzy Logic Control The apphcation of fuzzy logic to process control requires the concepts of Fuzzy rules and fuzzy inference. A fuzzy rule, also known as a fuzzy IF-THEN statement, has the form ... 

Income statements are veiy useful tools to assist management in controlling a business and planning for the future. Since management needs to follow the trends of the normal expenses, extraordinaiy expenses such as those incurred as a result of a major fire or flood should be shown separately. 

Bubble Policy The bubble concept introduced under PSD provisions of the Clean Air Act Amendments of 1977 was formally proposed as EPA policy on Jan. 18, 1979, the final policy statement being issued on Dec. 11, 1979. The bubble pohcy allows a company to find the most efficient way to control a plant s emissions as a whole rather than by meeting individual point-source requirements. If it is found less expensive to tighten control of a pollutant at one point and relax controls at another, this woiild be possible as long as the total pollution from the plant woiild not exceed the sum of the current hmits on individual point sources of pollution in the plant. Properly apphed, this approach would promote greater economic efficiency and increased technological innovation. 

Invoices statement of procedure for submitting invoices Quality Control explanation of responsibilities for analysis of supplied materials, finished product, and work in progress consequences of off-spec materials procedure for rework Process Ownership specification of who owns the process, degree of liability for remediation, procedure for review and approval of process changes... 

An appreciation of statistical results can be gained from a study conducted to support the first application of computer control for an ethylene oxide production unit at Union Carbide Corporation in 1958. For the above purpose, twenty years of production experience with many units was correlated by excellent statisticians who had no regard for kinetics or chemistry. In spite of this, they did excellent, although entirely empirical work. One statement they made was ... [ethane has a significant effect on ethylene oxide production.] This was rejected by most technical people because it did not appear to make any sense ethane did not react, did not chemisorb, and went through the reactor unchanged. 

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