For Each...Next Loops

The For Each...Next loop structure is similar to the For...Next loop structure, except that it executes the statements within the loop for each object within a group of objects. Figure 14-12 illustrates the syntax of the statement. 

An important point the For..Each...Next loop returns an object variable in each pass through the loop. You can access or use all of the properties or methods that apply to Element. For example, in a loop such as... 

Often you use a loop structure to search through an array or collection of objects, looking for a certain value or property. Once you find a match, you don t need to cycle through the rest of the loops. You can exit from the loop using the Exit For (from a For...Next loop or For Each...Next loop) or Exit Do (from a Do While... loop). The Exit statement will normally be located within an If statement. For example. 

The simple macro in Figure 16-1 formats the text in a single cell. We d like our macro to be able to format text in a single cell or in a range of cells. To do this, we simply need to add an outer For..Each...Next loop. We ll add the lines of code... 

To specify the range of cells to use as data labels, we ll use the InputBox method. We ll define the range as an object variable, so that we can use a For...Each...Next loop. For a code example, see "You Can Define Your Own Objects" in Chapter 14. To convert SeriesCollection(l) into the general case, remember that a specific item in a collection can be referred to by its index number or by its name. We ll use the code... 

This example illustrates how easy it is to use a For Each. .. Next loop to address ah cells in a given, highlighted block, even without ever specifying it as an array. The name cell specifies the individual cells in the highlighted block, and the loop addresses each of them in turn. (Any other name instead of cell would have worked just as well. You can see that cell is not recognized by the VBA compiler because it is not capitalized. (But Cells in... 

On the other hand, the macro Power disp enses with much of this, and simply condenses steps (b) through (e) into a simple, single For Each... Next loop. 

B2+ 1= 8 + 1 =9, hence we find the result 93 = 729 instead. In B4 the macro then computes 7303 = 3.87E + 08, and from there the size of the results quickly escalates to exceed the numerical capacity of the spreadsheet (approximately 9.9 X 10307) in B8, which is why we see the overflow sign. Therefore one should use For Each... Next loops only on cells containing values that are independent of all other data in the selected block. 

The For Each...Next loop is similar to a For... Next statement except that it will automatically apply the statements to each element of the specified group. The syntax is... 

For Each...Next loop 268 For...Next loop 268 form, custom 159 Format Cells dialog box 33 Format Painter toolbutton 34 formats, number... 

Organic synthesis, the powerful chemistry developed by humankind, still often uses a simple step-by-step approach to convert a starting material A into a final product D, in which intermediate products B and C are isolated and purified for each next conversion step (Fig. 13.1). Catalytic steps are mostly combined with stoichiometric steps in the preparation of precursors or in the further downstream processing. Obvious disadvantages are low space-time yields (kg L-1 h-1), laborious recycle loops and large amounts of waste. 

See also Do...Loop, Exit, For Each...Next, While...Wend... 

The cause of the problem lies in the numbers 3 and 113 used to raise the individual terms of the array to their cube power, and to take their cube root. When we raised the individual cells in the block (or the individual elements in Array) to their cube power, we reduced the results to single precision. To demonstrate this and, at the same time, fix the problem, add a dimension statement to both macros, reading Dim p As Double , and add a line specifying the value of p (e.g., either p = 3 or p =1/3 ). Finally, in the For Each... Next (or in the nested For... Next loop) refer to p rather than to 3 (or 1/3). The macros now should read like the example shown below, where we have also added a title and some comment lines and, as before, boldfaced the most recent changes. 

The goal of a DCS is to apply the control calculations for each control loop so quickly that the control appears continuous. Since DCSs are based on sequential processors, each control loop is applied at a discrete point in time, and the control action is held constant at that level until the next... 

LOOKUP (worksheet function) 82 Lookup Reference functions 81 lookup in table, with linear interpolation 171 Loop, Do While... (VBA) 268 loop, exiting from (VBA) 269 Loop, For Each...Next (VBA) 268 Loop, For...Next (VBA) 268 looping (VBA) 267 LOWER (worksheet function) 79... 

There are four looping statements in VBA (For...Next, Do While...Loop, Do...Loop While, For Each...Next). Only the first two of these are presented since the other two are repetitious (or can be confusing). 

This is implemented on lines 16 through 23 of the code. As an example, if is 4.0 and step is 2.0 the next iteration value will be limited to the range 2.0 and 8.0 a factor of 2 (step) below the value and a factor of 2 above the value. If the step parameter is 1.1 the new solution values will be limited to a change of approximately 10% around the previous value. Also a step size of less than unity is converted on line 7 to a value greater than unity so that step sizes of 0.5 and 2.0 have exactly the same effect. In addition to step size limits, the new listing also includes a print capability on line 26 for each iterative loop if the nprint variable is set to any value different from nil. 

The loop of the 2nd-D HPLC was loaded with the effluent from the lst-D HPLC at 50 pL/min for 3 min 53 s, then the injection valve was turned to inject the 200 pL fraction for 7 s onto the 2nd-D HPLC at 3 pL/min, and turned back for loading for the next 3 min 53 s, resulting in fractionation of the lst-D every 4 min. Thus, ca. 300 nL or 0.15% of each fraction from lst-D (200 pL) was introduced into the 2nd-D column having approximately 800 nL column volume. 

The decision for each example is expressed as an "action-next state" pair. The "action" is a reference to executable Radial code, which consists of a sequence of Radial statements. These statements may contain references to external programs in various languages (this will be discussed further later). The "next state" describes the context to which control is to pass after the action is completed. For diagnostic expert systems, such as TOGA, the next state will usually be the "goal" state of the module. This passes control back to the calling module. For procedural expert systems, such as robotics and instrumentation control applications, the control will be transferred between several states within a module to Implement looping. 

The smallest loops, as they occur in the networks at complete reaction, are Illustrated in Figure 3, together with the elastically active function points lost. For f=3, each smallest loop leads to the loss of two junction points and for f=4 only one junction point per smallest loop is lost. Notwithstanding that more complex ring structures will occur, the greater loss of junction points per smallest loop, and indeed per next smallest loop(16) for f=3 compared with f=4 networks is the basic reason why the former networks (curves 1 and 2 in Figure 1) show larger reductions in modulus per pre-gel loop than the latter networks (curves 3 to 6). 

After cycling once again through a complete hysteresis to ensure the same initial condition the excitation signal is stopped at the next voltage for the relaxation time. The relaxed polarization is again determined as described above. The whole procedure is repeated for each point until a complete quasi static hysteresis loop has been recorded. 

The description request flag in line 400 determines whether this section of the program is executed or skipped over. Remember that 0 indicates the latter. If it is 0, then, this entire routine is bypassed. If it is executed, describing the room consists simply of printing the appropriate element of the room descripion array. That s line 410. Then in line 430, a FOR-NEXT loop executes, which goes through each item in the item location array. For each item that s located in the current room (F = 0), it prints the corresponding element of the item description array (done in line 450 and 460). This way the player will see what each room contains. 

The next part of the program is a loop with 31 steps. The pressure is changed from 1, to 2, 3, 4,..., 31. For each pressure, the constants a and b are calculated, as aRK and bRK, respectively. Then specvol is called to find the specific volume for those conditions the answer is stored in the variable vol as an array, or vector. The compressibility factor is calculated and stored in the vector Z. Finally, a plot is made with pres along the v-axis and Z along the y-axis, The result is Figure 2.2. 

Below the assignment Array = Selection.Value we encounter two nested For Next loops. In each loop a calculation is repeated a specified number of times. In this example, each numerical value in the array is in turn raised to its cube power (or to any other power we might have specified instead of 3). Incidentally, note that the indentation used facilitates our reading of the macro, by showing what lines are involved in the two different loops. 

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