Difference between revisions of "Example function"

Revision as of 03:11, 21 March 2018

Analytica User GuideUser-defined Functions and LibrariesExample function

Here is a simple example of a user-defined function.

This function, Capm, computes the expected return for a stock under the capital asset pricing model:

Parameters

It has three parameters, «rf», «rm», and «beta». The parameter qualifier Number says that it expects that three parameters should be numbers (or arrays of numbers). If not, it will give a error message during evaluation.

Description

The description is documentation explaining what the function returns and what its parameters mean.

Definition

The definition is an expression that uses its parameters, «rf», «rm», and «beta», and computes the value to be returned.

Sample usage

You use the Capm() function in a definition in the same way you would use any built-in function. For example, if the risk free rate is 5%, the expected market return is 8%, and Stock-Beta is defined as the beta value for a given stock, we can find the expected return according to the capital asset pricing model as:

Stock_return: Capm(5%, 8%, StockBeta)

The function works equally well when StockBeta -- or any parameter -- is an array of numbers. The result is an array of expected returns.

@@ Line 2: / Line 2: @@
 [[Category: Functions]]
 <breadcrumbs>Analytica User Guide > User-defined Functions and Libraries > {{PAGENAME}}</breadcrumbs><br />
+Here is a simple example of a user-defined function.
 __TOC__
-The following function, [[Capm]], computes the expected return for a stock under the capital asset pricing model.
+This function, [[Capm]], computes the expected return for a stock under the capital asset pricing model:
-:[[File:example_function_1.png|400px]]
+:[[File:example_function_1.png|600px]]
-==Parameters==
+===Parameters===
-It has three [[Function calls and parameters|parameters]], «rf», «rm», and «beta». The [[parameter qualifiers|parameter qualifier]] <code>Number</code> says that it expects that the parameters are numbers.
+It has three [[Function calls and parameters|parameters]], «rf», «rm», and «beta». The [[parameter qualifiers|parameter qualifier]] <code>Number</code> says that it expects that three parameters should be numbers (or arrays of numbers). If not, it will give a error message during evaluation.
-==Description==
+===Description===
-The description says what the function returns and what its parameters mean.
+The description is documentation explaining what the function returns and what its parameters mean.
-==Definition==
+===Definition===
-The definition is an expression that uses its parameters, «rf», «rm», and «beta», and evaluates to the value to be returned.
+The definition is an expression that uses its parameters, «rf», «rm», and «beta», and computes the value to be returned.
-==Sample usage==
+===Sample usage===
-You use the [[Capm]]() function in a definition in the same way you would use Analytica’s built-in functions. For example, if the risk free rate is 5%, the expected market return is 8%, and <code>Stock-Beta</code> is defined as the beta value for a given stock, we can find the expected return according to the capital asset pricing model as:
+You use the [[Capm]]() function in a definition in the same way you would use any built-in function. For example, if the risk free rate is 5%, the expected market return is 8%, and <code>Stock-Beta</code> is defined as the beta value for a given stock, we can find the expected return according to the capital asset pricing model as:
 :<code>Stock_return: Capm(5%, 8%, StockBeta)</code>
-The function works equally well when <code>StockBeta</code> is an array of beta values — or if any parameter is an array. The result is an array of expected returns.
+The function works equally well when <code>StockBeta</code> -- or  any parameter -- is an array of numbers. The result is an array of expected returns.
 ==See Also==