英文字典中文字典


英文字典中文字典51ZiDian.com



中文字典辞典   英文字典 a   b   c   d   e   f   g   h   i   j   k   l   m   n   o   p   q   r   s   t   u   v   w   x   y   z       







请输入英文单字，中文词皆可：


请选择你想看的字典辞典：
单词字典翻译
expr查看　expr　在百度字典中的解释百度英翻中〔查看〕
expr查看　expr　在Google字典中的解释Google英翻中〔查看〕
expr查看　expr　在Yahoo字典中的解释Yahoo英翻中〔查看〕

安装中文字典英文字典查询工具!


中文字典英文字典工具:
选择颜色:
输入中英文单字

































































英文字典中文字典相关资料:


  • bash - Using expr, $ ( ()), ( ()) - Unix Linux Stack Exchange
    Here the expression will be calculated by the program expr, which isn't a shell builtin but an external Unix program So instead of simply adding 1 and s a program must be started und its output must be read and written to the variable
  • shell - Parenthesis in expr arithmetic: 3 * (2 + 1) - Unix Linux . . .
    Thus: expr 3 \* \( 2 + 1 \) Unless you're working on an antique unix system from the 1970s or 1980s, there is very little reason to use expr In the old days, shells didn't have a built-in way to perform arithmetic, and you had to call the expr utility instead All POSIX shells have built-in arithmetic via the arithmetic expansion syntax
  • Adding two numbers using expr - Unix Linux Stack Exchange
    expr is an external program used by Bourne shell (i e sh) Bourne shell didn't originally have any mechanism to perform simple arithmetic It uses expr external program with the help of backtick The backtick (`) is actually called command substitution Command substitution is the mechanism by which the shell performs a given set of commands and then substitutes their output in the place of
  • What is expr doing when processing arrays? - Unix Linux Stack Exchange
    1 Expr is a command line tool, it is independent from the bash It does not know anything about arrays It gets command line arguments, exactly those what we refer as $1, $2, $3 etc in our scripts Important thing is: bash knows arrays, but as you call a binary, it can only get a list of arguments as its parameters
  • Substring extraction with expr - Unix Linux Stack Exchange
    man expr says the "STRING : PATTERN" expression is "anchored", and then in the info page (info coreutils 'expr invocation') you can read: `STRING : REGEX' Perform pattern matching The arguments are converted to strings and the second is considered to be a (basic, a la GNU `grep') regular expression, with a `^' implicitly prepended The first argument is then matched against this regular
  • shell - How to do integer float calculations, in bash or other . . .
    Using echo "20+5" literally produces the text " 20+5 " What command can I use to get the numeric sum, 25 in this case? Also, what's the easiest way to do it just using bash for floating point? For example, echo $((3224 3807 0)) prints 0 : ( I am looking for answers using either the basic command shell ('command line') itself or through using languages that are available from the command line
  • string - Zsh equivalent of bashs `expr index . . .
    What would be Zsh equivalent of bash's expr index "abcdefghijklmnopqrstuvwxyz" xyzd I am trying to find index of substring
  • shell script - OR in `expr match` - Unix Linux Stack Exchange
    I'm confused as to why this does not match: expr match Unauthenticated123 '^(Unauthenticated|Authenticated) *' it outputs 0
  • bash - Arithmetic operations with expr and variables - Unix Linux . . .
    The expr command can only do integer or string manipulations Look at the man page for this guidance: Operands are either integers or strings Integers consist of one or more decimal digits, with an optional leading '-' 'expr' converts anything appearing in an operand position to an integer or a string depending on the operation being applied to it So to perform this type of operation you'll
  • expr - How to add mathematically the results of two commands in Linux . . .
    I note that expr is considered archaic and obsolete It has two main uses, arithmetic and regex matching, both of which are available in most shells (By the by, "Debian Linux shell" isn't just one thing; it could be Bash or Dash or indeed whichever shell is chosen when the user is added or changed subsequent )





中文字典-英文字典  2005-2009