{{tag>Programmers_Reference Methods IFunctionLibrary_Interface getRequiredFactPatterns Index}}

====getRequiredFactPatterns (String, Collection)====
<code java>public HashSet getRequiredFactPatterns (String functionName, Collection parameters)</code>

===Parameters===
|''functionName''|the name of the function in the library the return type of which is required.|
|''parameters''|the parameters of the function specified as a collection of the ''IArithmeticNode'' objects. |

===Returns===
This method should have no implementation and return ''null''.