home | O'Reilly's CD bookshelfs | FreeBSD | Linux | Cisco | Cisco Exam    

UNIX Power Tools

UNIX Power ToolsSearch this book
Previous: 49.1 bc: Simple Math at the Shell Prompt Chapter 49
Working with Numbers
Next: 49.3 Gotchas in Base Conversion
 

49.2 bc: Hexadecimal or Binary Conversion

One thing that's really handy to know about bc is how to use it for base conversion.

By default, bc takes its input and prints its output in decimal. However, you can set either the input or the output to be some other base numbering system - for example, hexadecimal or binary - using the ibase and obase commands.

For example, to find the decimal equivalents to a hexadecimal number, set ibase to 16, and leave obase alone (i.e., as decimal). Simply type the number (or a series of numbers separated by semicolons) you want converted, and press RETURN. The decimal equivalent will be printed below. (Hexadecimal numbers from A to F must be typed in uppercase, or bc will report an error.) For example:

% 

bc
ibase=16
B6;7F;FFF


182
127
4095

Or if you wanted to convert to hexadecimal, you'd set obase to 16, and leave ibase at 10:

% 

bc
obase=16
142


8E

Or, to convert binary to hexadecimal, set ibase=2 and obase=16 (or ibase=16 and obase=2 for the reverse operation):

% 

bc
obase=16
ibase=2
11010001


D1

Type CTRL-d to exit bc . Be careful to set obase before ibase , or you will have problems ( 49.3 ) .

- TOR


Previous: 49.1 bc: Simple Math at the Shell Prompt UNIX Power Tools Next: 49.3 Gotchas in Base Conversion
49.1 bc: Simple Math at the Shell Prompt Book Index 49.3 Gotchas in Base Conversion

The UNIX CD Bookshelf Navigation The UNIX CD BookshelfUNIX Power ToolsUNIX in a NutshellLearning the vi Editorsed & awkLearning the Korn ShellLearning the UNIX Operating System










??????????????@Mail.ru