tailieunhanh - Excel 2002 Formulas phần 7

Nếu công thức của bạn sử dụng một chức năng mà đòi hỏi một loạt các tài liệu tham khảo, bạn có thể thay thế tài liệu tham khảo nhiều với một mảng liên tục. Điều này rất hữu ích trong các tình huống trong đó các giá trị trong phạm vi tham chiếu không thay đổi. | Chapter 17 Charting Techniques 481 Here s how it works. Select an individual data point in a chart series not the entire series and then drag the point in the direction in which you want to adjust the value. As you drag the data marker the corresponding value in the worksheet changes to correspond to the data point s new position on the chart. If the value of a data point that you move is the result of a formula Excel displays its Goal Seek dialog box. Use this dialog box to specify the cell that Excel should adjust to make the formula produce the result that you pointed out on the chart. This technique is useful if you know what a chart should look like and you want to determine the values that will produce the chart. Obviously this feature can be dangerous because you inadvertently can change values that you shouldn t so exercise caution. Using Animated Charts Most people don t realize it but Excel is capable of performing simple animations using shapes and charts animations require macros . Consider the XY chart shown in Figure 17-30. Figure 17-30 A simple VBA procedure turns this chart into an interesting animation. The x values column A depend on the value in cell A1. The value in each row represents the previous row s value plus the value in A1. Column B contains formulas that calculate the SIN of the corresponding value in column A. The following simple procedure produces an interesting animation. It simply changes the value in cell A1 which causes the values in the x and y ranges to change. 482 Part V Miscellaneous Formula Techniques Sub AnimateChart Range A1 0 For i 1 To 150 Range A1 Range A1 Next i Range A1 0 End Sub ON THE CD The companion CD-ROM contains a workbook that features this animated chart plus several other animation examples. Creating a Gauge Chart Figure 17-31 shows what appears to be a new chart type that resembles a gauge. Actually it s a standard pie chart but with one hidden slice. The hidden slice occupies 50 percent of the chart