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Top Forums UNIX for Dummies Questions & Answers Trying a arithmatic on a command line vs scripting. Post 302338221 by CasperQuiet on Monday 27th of July 2009 09:56:18 AM
Old 07-27-2009
Trying a arithmatic on a command line vs scripting.

Hi Everyone!
I'm trying to do simple math on a single command line instead of a script which I've already set up using let etc. I can not get the same output to display on a command line.

Essentially I would like a=20, b=50, and c=a*b.

When I tried:
let "A=20, B=50"; let C=A*B; echo $C

I got the answer but the following error message:
-bash: let: 1000=A*B; attempted assignment to non-varible (error token is "=A*B")

I didn't know if that meant to add quotes in the formula...so i tried that and it didn't work either. Where am i making the mistake?

Thanks so much!
 
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QUIZ(6) 							 BSD Games Manual							   QUIZ(6)

NAME
quiz -- random knowledge tests SYNOPSIS
quiz [-t] [-i file] [question answer] DESCRIPTION
The quiz utility tests your knowledge of random facts. It has a database of subjects from which you can choose. With no arguments, quiz displays the list of available subjects. The options are as follows: -t Use tutorial mode, in which questions are repeated later if you didn't get them right the first time, and new questions are presented less frequently to help you learn the older ones. -i Specify an alternative index file. Subjects are divided into categories. You can pick any two categories from the same subject. quiz will ask questions from the first cate- gory and it expects answers from the second category. For example, the command ``quiz victim killer'' asks questions which are the names of victims, and expects you to answer with the cause of their untimely demise, whereas the command ``quiz killer victim'' works the other way around. If you get the answer wrong, quiz lets you try again. To see the right answer, enter a blank line. Index and Data File Syntax The index and data files have a similar syntax. Lines in them consist of several categories separated by colons. The categories are regular expressions formed using the following meta-characters: pat|pat alternative patterns {pat} optional pattern [pat] delimiters, as in pat[pat|pat]pat In an index file, each line represents a subject. The first category in each subject is the pathname of the data file for the subject. The remaining categories are regular expressions for the titles of each category in the subject. In data files, each line represents a question/answer set. Each category is the information for the question/answer for that category. The backslash character (``'') is used to quote syntactically significant characters, or at the end of a line to signify that a continuation line follows. If either a question or its answer is empty, quiz will refrain from asking it. FILES
/usr/share/games/bsdgames/quiz The default index and data files. BUGS
quiz is pretty cynical about certain subjects. BSD
May 31, 1993 BSD

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