Array indexing

Use sliders for Npiate, Fplate and R to determine the optimum design conditions for the column. For this the array index [i] can be chosen for the X axis to obtain steady-state axial profiles. 

Stagewise and finite-differenced models involve changes with time and distance. When the model is written in array form the variable can be plotted as a function of the array index. This is done by choosing an index variable for the Y axis and the [ ] symbol for the X axis. The last value calculated is used in the plot, which means that if the steady-state has been reached then it is a steady-state profile with distance. An example is given in the Screenshot Guide in Section 2 of the Appendix and in many other simulation examples. 

Excel Tip. Since worksheet ranges, worksheet functions and worksheet arrays use (or assume) a lower array index of 1, you should always include the Option Base 1 statement at the beginning of each code module that uses arrays. 

The lower index of these arrays is always 1. Although arrays created within VBA have a lower array index of zero unless specified otherwise (by means of the Option Base 1 statement, for example), when you transfer a range of cells from a worksheet to VBA, an array is created with lower array index of 1. 

If you use a worksheet function within VBA that returns an array, the lower array index will be 1. Such worksheet functions include LI NEST, TRANSPOSE, MINVERSE, MMULT. Other functions that return arrays include the VBA function Caller when used with a menu command or toolbutton. 

Since FINEST requires that there be the same number of values for each independent variable, we first check to make sure that each range in the array of arguments has the same number of rows. An interesting point although we specified Option Base 1, the ParamArray keyword produces an array whose lower array index is zero. Thus we must loop from 0 to UBound(rng). Note that UBound(rng) is the number of elements in the array, while... 

Figure 12. From the same program as Fig. 11, the last (steady-state) values of B[ ] are plotted versus the array index [i] as an overlay. This feature can be used to plot axial or length profiles for stagewise or finite-differenced models.

It is easy to use a while loop to step through a series of values. For example, the following while loop zeroes the first ten elements of an array named x. (An integer variable named i is used as the array index and as the loop counter.)... 

A variety of strategies can be implemented in a compiler (or pre-compiler) to apply PAROS. At present, we have studied the usage of array-indexing variables, as was depicted in the example above. Before proceeding to further strategies we will evaluate the statistics on the usage of integer variables (see Section 5.3). 

Accesses to arrays and ports are automatically converted to functional unit calls. For example, suppose we have an FU named mm, described in Vhdl as an array (thus it is represented as a memory device in hardware, the array index being the address). Assignments to ram in the initial description would then be replaced by WRITE requests, and if ram was used as an operand in some operation, this would be replaced by a READ function. For our control-flow-dominated target domain, we have chosen to realize the memory access as implied by the Vhdl description. No memory-oriented loop optimizations, as addressed in chapter 7 and 8, are foreseen here. 

If, on the other hand, the details of the IR and the target machine are similar, the problem is much simpler. With a low-level, linear IR and a typical RISC microprocessor, much of the code might be handled with a one-to-one mapping of IR operations into machine operations. The low-level IR already introduces registers (albeit an unlimited number), expands abstractions like array indexing into their component operations, and includes the temporary names required to stitch binary operations into more... 

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