How to embed form into my single.php page

If you go to the Help page within Gravity Forms it shows how to use the shortcode to insert a form into a page or post without editing a theme file.

It also shows how to use the function call to display a form by adding this code to your theme file. This is more advanced usage, we usually recommend using shortcodes unless there is a specific reason as to why it needs to be hardcoded into your theme.

The documentation can also be found within the Documentation area on this site:

http://www.gravityhelp.com/documentation/embedding-a-form/

You don't have to put anything in your functions.php file.

The article kevin pointed out in the documentation explains the function call you would use in your single.php theme file. It would look like this:

<?php gravity_form(X, true, true); ?>

The "X" would be replaced with the id of the form you want to call. The first true is if you want to display the form title and the second true is if you want to display the form description. These values can both be false.

It's explains on this page under "Function Call":

http://www.gravityhelp.com/documentation/embedding-a-form/

Is there any reason why you want to hardcode the form in your theme template files instead of using the shortcode and inserting the form in a post or page when you create the post or page?