Function SCIPsetHeuristics 

pub unsafe extern "C" fn SCIPsetHeuristics(
    scip: *mut SCIP,
    paramsetting: SCIP_PARAMSETTING,
    quiet: c_uint,
) -> SCIP_RETCODE

sets heuristic parameters values to

• SCIP_PARAMSETTING_DEFAULT which are the default values of all heuristic parameters
• SCIP_PARAMSETTING_FAST such that the time spend for heuristic is decreased
• SCIP_PARAMSETTING_AGGRESSIVE such that the heuristic are called more aggregative
• SCIP_PARAMSETTING_OFF which turn off all heuristics

@note: Using SCIP_PARAMSETTING_AGGRESSIVE enables heuristics regardless of the USESSUBSCIP flag, which could lead to unintended recursion when applied to a subscip.

@return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref SCIP_Retcode “SCIP_RETCODE” for a complete list of error codes.