Selecting from the Prism equation library

You are not limited to the classic equations built-in to Prism. You can also enter your own equation (see  User-defined equations) or choose an equation from an equation library. To choose an equation from a library, click "more equations" (from the parameters dialog for nonlinear regression), then choose to select from the equation library.

On the Equation Selection dialog,  first choose a library file (left panel) then choose an equation (right panel). Confirm your choice with the preview on the bottom of the dialog.

When you select an equation from the library, you transfer it from the library file to your own list of equations. You can then edit that copy of the equation without affecting the library. Prism stores the equation with every file that uses it, and also places the equation in your list of user-defined equations (the list you see when you choose "more equations"). Prism does not remember that the equation came from a library.

GraphPad may extend the equation library over time. Check www.graphpad.com for new equations. You can add equation files to your equation library. Simply save a Prism file or template into the equations folder.

Importing an equation from another Prism project

You can import any equation from any project. Click "more equations" (from the parameters dialog for nonlinear regression). Choose to import an equation and select a file and an equation.

When you import an equation, you transfer to your own list of equations (the list you see when you choose "more equations"). Prism does not store any sort of link back to the file the equation was imported from.

Managing your list of equations

When you choose "more equations", Prism shows you a list of equations you have entered or imported. If you don't plan to use an equation again, select it and click Delete to erase it from the list. That won't affect any files that use the equation you erased. If you open one of these files, and change the parameters of the nonlinear regression, Prism will automatically add the equation back to your list.

You can change the order of equations in your list by selecting an equation and then clicking Move up or Move down.

Modifying equations

You can edit any equation you entered yourself or imported (or chose from the equation library). From the nonlinear regression parameters dialog, select the equation from the list of "more equations" and then click Edit Eqn.Classic equations cannot be modified. But you can create a new user-defined equation based on a classic equation.

To copy and paste a built-in equation:

1. Start from the Nonlinear Regression or Simulate Equation Parameters dialog.

2. Select a built-in classic equation, and click on the button labeled "Equation".

3. Press the button labeled "Copy All".

4. Cancel from that dialog.

5. Select "More equations", then "enter a new equation".

6. Enter an equation name. Then move the insertion point to the Equation block.

7. Press the button labeled "Paste".

8. Edit the equation.