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git diff myfile.txt Shows the changes between the previous commit of the specified file (myfile.txt) and the locally-modified version that has not yet been staged. This also works for directories: git diff documentation The above shows the changes between the previous commit of all files in ...

Suppose you have a Dockerfile ending with ENTRYPOINT [ "nethogs"] CMD ["wlan0"] if you build this image with a docker built -t inspector . launch the image built with such a Dockerfile with a command such as docker run -it --net=host --rm inspector ,nethogs will monitor the...

Python makes it very simple to check whether an item is in a list. Simply use the in operator. lst = ['test', 'twest', 'tweast', 'treast'] 'test' in lst # Out: True 'toast' in lst # Out: False Note: the in operator on sets is asymptotically faster than on lists. If you need to use it ...

To execute operations in a container, use the docker exec command. Sometimes this is called "entering the container" as all commands are executed inside the container. docker exec -it container_id bash or docker exec -it container_id /bin/sh And now you have a shell in your running...

There are two ways to achieve that, the first and most known is the following: docker attach --sig-proxy=false <container> This one literally attaches your bash to the container bash, meaning that if you have a running script, you will see the result. To detach, just type: Ctl-P Ctl-Q Bu...

We plot a simple scatter plot using the builtin iris data set as follows: library(ggplot2) ggplot(iris, aes(x = Petal.Width, y = Petal.Length, color = Species)) + geom_point() This gives:

There are different cases where you must Explicitly specify the type parameters for a generic method. In both of the below cases, the compiler is not able to infer all of the type parameters from the specified method parameters. One case is when there are no parameters: public void SomeMethod<T...

To get all the information for a container you can run: docker inspect <container>

You can get an specific information from a container by running: docker inspect -f '<format>' <container> For instance, you can get the Network Settings by running: docker inspect -f '{{ .NetworkSettings }}' <container> You can also get just the IP address: docker inspect ...

Sometimes you need rewrite history with a rebase, but git push complains about doing so because you rewrote history. This can be solved with a git push --force, but consider git push --force-with-lease, indicating that you want the push to fail if the local remote-tracking branch differs from the b...

The job of the linker is to link together a bunch of object files (.o files) into a binary executable. The process of linking mainly involves resolving symbolic addresses to numerical addresses. The result of the link process is normally an executable program. During the link process, the linker wi...

After the C pre-processor has included all the header files and expanded all macros, the compiler can compile the program. It does this by turning the C source code into an object code file, which is a file ending in .o which contains the binary version of the source code. Object code is not directl...

Sometimes it's necessary to convert a Discriminated Union to and from a string: module UnionConversion open Microsoft.FSharp.Reflection let toString (x: 'a) = match FSharpValue.GetUnionFields(x, typeof<'a>) with | case, _ -> case.Name let fromStri...

Given the text: foo: bar I would like to replace anything following "foo: " with "baz", but I want to keep "foo: ". This could be done with a capturing group like this: s/(foo: ).*/$1baz/ Which results in the text: foo: baz Example 1 or we could use \K,...

The order of keys in Python dictionaries is arbitrary: they are not governed by the order in which you add them. For example: >>> d = {'foo': 5, 'bar': 6} >>> print(d) {'foo': 5, 'bar': 6} >>> d['baz'] = 7 >>> print(a) {'baz': 7, 'foo': 5, 'bar': 6} >&g...

Table Setup CREATE TABLE dbo.Employees ( EmployeeID INT NOT NULL PRIMARY KEY, FirstName NVARCHAR(50) NOT NULL, LastName NVARCHAR(50) NOT NULL, ManagerID INT NULL ) GO INSERT INTO Employees VALUES (101, 'Ken', 'Sánchez', NULL) INSERT INTO Employees VALUES (102, 'Keith', ...

Functions can modify the parameters passed to them if they are marked with the inout keyword. When passing an inout parameter to a function, the caller must add a & to the variable being passed. func updateFruit(fruit: inout Int) { fruit -= 1 } var apples = 30 // Prints "There's 3...

string[] names= { "mark", "steve", "adam" }; Ascending: Query Syntax var sortedNames = from name in names orderby name select name; Method Syntax var sortedNames = names.OrderBy(name => name); sortedNames contains the names in following ord...

Floating point numbers of type real cannot have any real value. They can represent real numbers up to certain amount of decimal digits. FORTRAN 77 guaranteed two floating point types and more recent standards guarantee at least two real types. Real variables may be declared as real x double prec...

There are a couple ways you can reverse a string to make it backwards. StringBuilder/StringBuffer: String code = "code"; System.out.println(code); StringBuilder sb = new StringBuilder(code); code = sb.reverse().toString(); System.out.println(code); Char array: S...