tailieunhanh - AutoCAD Basics 2004 bible phần 2

Loại Xây Dựng Kiến Trúc đơn vị thập phân Fractional khoa học mẫu đo 32,50 2'-8 0,50 2'-8 02/01 32 02/01 01 Mô tả Số đơn vị, đơn vị một phần số thập phân Feet và inch, inch một phần Feet số thập phân và inch, inch một phần trong phân số số đơn vị, đơn vị một phần trong số các phân số cơ bản + số mũ | 90 Part I AutoCAD Basics Table 5-1 Unit Types Unit Type Sample Measurement Description Decimal Number of units partial units in decimals Engineering 2 Feet and inches partial inches in decimals Architectural 2 -8 1 2 Feet and inches partial inches in fractions Fractional 32 1 2 Number of units partial units in fractions Scientific 01 Base number exponent Note If you are using engineering or architectural units AutoCAD displays partial inches differently than the format you must use to type them in. You must type coordinates without any spaces because AutoCAD interprets a space as equivalent to pressing the Enter key and ends your input. Use a hyphen between whole and partial inches for example 3 2-1 2 . You can omit the after the inches because AutoCAD assumes inches in engineering and architectural units if no symbol follows a number. However this appears on the status line as 3 -2 1 2 . This can be confusing because the hyphen is in a different place and AutoCAD inserts a space between the whole and partial inches. Setting the drawing units Once you know the units you want to use you set them in the Drawing Units dialog box. To set the units choose Format Units to open the Drawing Units dialog box shown in Figure 5-1. The left side of the Drawing Units dialog box enables you to choose which unit type you want to use. In the Precision box in the Length section click the arrow and a list of precision options drops down. Click the one you want. Figure 5-1 The Drawing Units dialog box Chapter 5 Setting Up a Drawing 91 Look in Chapter 3 for a brief overview of the Drawing Units dialog box in the exercise on using a dialog box. See Chapter 18 for more on inserting drawings into other drawings by using the DesignCenter. See Chapter 26 for full coverage on the DesignCenter. AutoCAD rounds off measurements to the nearest precision value you choose. Say that you choose a precision of two decimal places using decimal units. You want to draw a line so that