--Originally published at Carolina's Blog Site

Opening Files

You can use Python to read and write the contents of files. Before a file can be edited, it must be opened, using the open function.

myfile = open(“filename.txt”)

The first argument of the open function is the path to the file (however, if the file is in the same directory as the program, you can specify only its name).

The second argument is the mode used to open a file.
“r” means open in read mode, which is the default.
“w” means write mode, for rewriting the contents of a file.
“a” means append mode, for adding new content to the end of the file.

Adding “b” to a mode opens it in binary mode, which is used for non-text files (like image and sound files).

Once a file has been opened and used, you should close it.
This is done with the close method of the file object.

file.close()

Reading Files

The contents of a file that has been opened in text mode can be read using the read method. Here are some other methods:

>>> f.read()
'This is the entire file.\n'

>>> f.readline()
'This is the first line of the file.\n'
>>> f.readline()
'Second line of the file\n'
Or you can create a for loop:

>>> for line in f:
...     print(line, end='')

Other stuff

To write to files you use the write method, which writes a string to the file.

You should know, when a file is opened in write mode, the file’s existing content is deleted.

Another way of working with files is using with statements. This creates a temporary variable (often called f), which is only accessible in the indented block of the with statement.with open(“filename.txt”) as f:

print(f.read())
The file is automatically closed at the end of the with statement, even if exceptions occur within it; this can save you a lot of problems.

Hope this was helpful!!

sources:

https://docs.python.org/3/tutorial/inputoutput.html

https://www.memecenter.com/fun/2363511/i-amp-039-m-losing-my-voice/comments

--Originally published at Carolina's Blog Site

So today I made a function that asks the user for 2 integers and then displays the Greatest Common Denominator, which is the largest number that divides both of them without leaving a reminder. I realized there’s several ways to do this, but I think this one’s pretty simple. It took me awhile to get it though. I just couldn’t make sense of it! Thank goodness I have fellow programmer friends who can explain theses sorta things to me

--Originally published at Carolina's Blog Site

A function is a named sequence of statements that performs an operation/computation. Functions may or may not take arguments (which are like the ingredients that change depending on what result you want to achieve in that particular occasion).

To define a function,

• you write def followed by the name of the function,
• then you write the parameters/arguments in () and you end with a “:”
• In the body of the function, which has to be indented, you type the order of the statements you want that function to do.
• To finish off a function, type return and specify what the function will return. If you don’t want to return anything, just leave the return line blank with (). Any code after the return statement will not happen.

Later, you can “call” the function by its name, and just type the parameters for that occasion. I know, awesome!

Side note:

• Parameters can have a default value, for example: (parameter1, parameter2, parameter3=55).
• If a function is a thing and parameters can be anything…then functions can also be used as parameters of other functions.

 

pic souce: http://www.relatably.com/m/functional-programming-memes