PyCharm 2017.1 Help

Creating and Running Your First Python Project

In this section:

Before you start

Make sure that the following prerequisites are met:

  • You are working with PyCharm CE or Professional.
  • You have installed Python itself. If you’re using macOS or Linux, your computer already has Python installed. You can get Python from

Creating a simple Python project in PyCharm

To get started with PyCharm, let’s write a Python script.

Do you remember the quadratic formula from math class? This formula is also known as the A, B, C formula, it’s used for solving a simple quadratic equation: ax2 + bx + c = 0. As manually solving quadratic formulas gets boring quickly, let’s replace it with a script.

Note that PyCharm suggests several project templates for the development of the various types of applications (Django, Google AppEngine, etc.). When PyCharm creates a new project from a project template, it produces the corresponding directory structure and specific files.

Let’s start our project: if you’re on the Welcome screen, click Create New Project. If you’ve already got a project open, choose File | New Project.

PyCharm suggests several project templates for the creation of the various types of applications (Django, Google AppEngine, etc.). When PyCharm creates a new project from a project template, it produces the corresponding directory structure and specific files, and any needed run configurations or settings.

In this tutorial we’ll create a simple Python script, so we’ll choose Pure Python. This template will create an empty project for us.

Choose the project location. To do that, click the browse button /help/img/idea/2017.1/browseButton.png next to the Location field, and specify the directory for your project.

Side note

Choosing which interpreter to use for a project is an important decision. Python is a script language, which means that your code is converted to machine code by a Python interpreter.

You can have multiple versions of Python installed on your computer, and you need to choose the one you’d like for this project. Refer to the section Configuring Python SDK for details. Note that you can always change your mind later and specify another interpreter for your project.

When you’re using external libraries (from PyPI or elsewhere) you need to manage the versions of these as well. The Pythonic solution for this are virtualenvs (sometimes abbreviated to venv). Virtualenvs help you keep the dependencies for your different projects separate. Although in this project we’re not using any dependencies, it’s considered best practice to create a virtualenv for every new project you make, in case you’d like to add dependencies in the future.

Python best practice is to create a virtualenv for each project. To do that, click /help/img/idea/2017.1/cogwheel_framed.png, choose Create VirtualEnv, and then specify the virtual environment’s name and location, and the base interpreter. For more information, see Creating Virtual Environment .

Then click Create.


If you’ve already got a project open, after clicking Create PyCharm will ask you whether to open a new project in the current window or in a new one. Choose Open in current window - this will close the current project, but you'll be able to reopen it later. Refer to the page Opening Multiple Projects for details.

Creating a Python file

Select project root in the Project tool window, and press Alt+Insert.


Choose the option Python file from the pop-up window, and then type the new file name Solver. PyCharm creates a new Python file and opens it for editing.


Editing source code

Let us first have a look at the Python file we've just generated.

Immediately as you start typing, you understand that PyCharm, like a pair-programmer, looks over your shoulder and suggests how to complete your line. For example, you want to create a Python class. As you just start typing the keyword, a suggestion list appears:


Choose the keyword class and type the class name (Solver). PyCharm immediately informs you about the missing colon, then expected indentation:


Note the error stripes in the right gutter. Hover your mouse pointer over an error stripe, and PyCharm shows a balloon with the detailed explanation. Since PyCharm analyses your code on-the-fly, the results are immediately shown in the inspection indicator on top of the right gutter.

This inspection indication works like a traffic light: when it is green, everything is OK, and you can go on with your code; a yellow light means some minor problems that however will not affect compilation; but when the light is red, it means that you have some serious errors.

Let's continue creating the function demo: when you just type the opening brace, PyCharm creates the entire code construct (mandatory parameter self, closing brace and colon), and provides proper indentation:


Note as you type, that unused symbols are greyed out:


As soon as you calculate a discriminant, they are rendered as usual. Next, pay attention to the unresolved reference math. PyCharm underlines it with the red curvy line, and shows the red bulb.

Let's make a brief excursion into PyCharm's notion of intention actions and quick fixes. When you write your code, it is sometimes advisable to modify code constructs - in this case PyCharm shows a yellow light bulb. However, if PyCharm encounters an error, it shows the red light bulb.

In either case, to see what does PyCharm suggest you to do, press Alt+Enter - this will display the suggestion list, which in our case contains several possible solutions:


Let's choose importing the math library. Import statement is added to the file. Next, calculate roots of the quadratic equation, and print them out, and finally, let's call the function demo of the class Solver:

import math class Solver: def demo(self): a = int(input("a ")) b = int(input("b ")) c = int(input("c ")) d = b ** 2 - 4 * a * c disc = math.sqrt(d) root1 = (-b + disc) / (2 * a) root2 = (-b - disc) / (2 * a) print(root1, root2) Solver().demo()

Running application

Next, right-click the editor, and on the context menu choose to run the script (Ctrl+Shift+F10). A console appears in the Run tool window.

Let’s try out our code by calculating the roots of 3x2 + 5x - 4. So enter a = 3, b = 5, and c = -4, and you should see a result:


Run/debug configuration

When we ran the script just now, PyCharm created a temporary run/debug configuration for us. Let’s first save this configuration: go to the run configuration dropdown on the top-right of the editor, and choose Save configuration.


Afterwards, choose Edit Configurations to have a look at what is happening here.


Note that there are different configuration types for unit testing, and the various frameworks (like Django in PyCharm Professional).

If you’d like to change how your program is executed by PyCharm, this is where you can configure various settings like: command-line parameters, work directory, and more. See Run/Debug configurations for more details.

If you’d like to start the script using this Run configuration, use the button /help/img/idea/2017.1/run.png next to the dropdown.

Congratulations on completing your first script in PyCharm! Learn how to debug your programs in PyCharm.

See Also

Last modified: 26 July 2017