apt cookbook

1. The default parameters of the function must be immutableIf the default parameter of a function is a mutable object, then the default parameter is modified outside the function and affects the function itself.def spam (A, b=None): # B to be an immutable parameter, you cannot use a variable parameter such as an empty list [] ... if is None: ... = []...2. Anonymous functions1. You can use anonymous functions when you can't think of a function name or want a short operationLambda

Cat/etc/issueCat/etc/redhat-release rpm-qa| grep releaseView versionUname-a-i-r View kernel versionYum Grouplistlang=enYum grouplist This command to list all installed and not installed packagesReboot;init 6 Shutdown-r now offSingle-run mode change passwordpasswd Change PasswordRestart linux,3 seconds, press ENTER. If you have a grub password, you need to press P first, enter the password before you can do the followingPress E, select the second row, and then press eadd single or number 1 or let

string-S: Replace duplicate characters!Example: [Root @test/root]# Last | TR ' [A-z] ' [A-z] ' [Root @test/root]# cat/etc/passwd | Tr-d: [Root @test/root]# Cat/home/test/dostxt | Tr-d ' \ r ' > Dostxt-nomSplitSyntax: [Root @test/root]# split [-BL] input file output file leading characterParameter description:-B: Divide by file size-L: divided by the number of rowsExample: [Root @test/root]# split-l 5/etc/passwd test Description: It's a lot easier under Linux! If you want to split the file, then

14.10 re-throw the caught exception?You caught an except exception in a block and now want to re-throw it.Solution?Simply use a single rasie statement, for example:>>>DefExample():...Try:...int ( ' n/a ' ) ... except valueerror: ... print ( "didn ' t work" ) ... raise ... >>> example () didn ' t work traceback (most recent call last): File "1, in span class= "n" > "3, in Examplevalueerror: invalid literal for int. () with base: ' N/a ' > >> Discuss?The problem is usually when y

), which provides CLI programs with a virtual machine environment that uploads and runs managed code on a variety of possible platforms, is just a specification, for example, Microsoft and Momo have their own implementations. The JIT and GC of the CLR for net should fall into this scope.The. NET Framework is a Microsoft implementation of the CLI, and, of course, the best implementation of the present, the. NET Framework mainly includes the CLR and the BCL,CLR is the core of the implementation of

operation time complexity is O (log N), where n is the size of the heap, so even when N is very large, they are still running fast. In the above code, the queue contains a tuple (-priority, index, item). The goal of a negative priority is to make the element sort from highest to lowest priority. This sort of heap is the opposite of regular sort by priority from low to high. The role of the index variable is to ensure that the same priority elements are sorted correctly. By saving an ever-increa

a Python object to the corresponding C parameter.This section of code uses Python's caching protocol to match any input parameter that looks like a double-precision array(such as numpy arrays, arrays created by array modules, etc.), refer to section 15.3 for more information.Inside the TYPEMAP code, variable substitution such as $ and $ will get the C parameter value of Typemap mode(for example, map to double*a ). $input point to a parameter as input PyObject* ,And $argnum it represents the num

;Fromllvm.eeImportExecutionengine>>>Engine=Executionengine.New(MoD)>>>Ptr=Engine.Get_pointer_to_function(F)>>>Ptr4325863440>>>Foo=cTYPES.Cfunctype(cTYPES.C_double,cTYPES.c_doublectypes. C_double) (ptr) >>> # Call the resulting Function>>> foo (23) 13.0>>> foo (4,5) Span class= "Go" >41.0>>> foo (1 ,2) 5.0>>> It's not that making any mistakes at this level will cause the Python interpreter to hang up.Remember that you are dealing directly with machine-level memory addresses and local machine c

1. Traversing a stringThere is no iterative operation in SQL, so you can implement this process by connecting a table that is used as a traversal pointer.1 Selectsubstr (E.ename, Iter.pos,1) asC2 from(SelectEname fromEmpwhereEname= 'KING') E,3(SelectId asPos fromT10) ITER4 whereIter.posLength (e.ename);There are 10 data in T10, ID from 1-10.The FROM clause provides a Cartesian product, and the resulting table resemblesThe WHERE clause restricts the POS range. SQL

Preface What method do you use to manage your rpm, install it from an optical disk, download and install it from the network, or maintain it using Red Hat's up2date (Red Hat Network, but you can have a better choice -- Apt I. IntroductionRedHat adopts the RPM software package management system. The RPM software package management system has powerful compilation and installation functions. However, due to historical reasons, the RPM software packag

Introduction: At the beginning, we had to compile the program we wanted to use on the GNU/Linux system. after Debian appeared, he thought that a method must be included in the system to manage the software packages that we have installed on our machines. this system is named dpkg. so the first time the famous package went into the GNU/Linux system, it was a long time before Red Hat decided to develop their own RPM package management system. However, a new dilemma lies in the face of GNU/Linux de

I. Preface 1.1 What is apt Installing new software is essential after the new operating system is installed. However, in Linux, the installation of application software is somewhat different from that in windows. For Linux beginners, installing software is a headache. Many Linux applications are released in the form of source code, which requires you to configure and compile the source program based on the actual situation of your system and your own

Apt-get command in Ubuntu Linux system (Via|via)Common APT Command parameters:　Apt-cache Search Package　Apt-cache Show package for information about packages, such as description, size, version, etc.　sudo apt-get install package　sudo apt