Initializing help system before first use

# problem.iisall

Purpose
This subroutine is deprecated and will be removed in a future release. Use problem.IISAll instead.
Performs an automated search for independent Irreducible Infeasible Sets (IIS) in an infeasible problem.
Synopsis
`problem.iisall()`
Example
This example searches for IISs and then questions the problem attribute NUMIIS to determine how many were found:

    p.iisall()
    print("The problem has {0} IISs".format(p.attributes.numiis))

Further information
1. A model may have several infeasibilities. Repairing a single IIS may not make the model feasible. For this reason the Optimizer can find an IIS for each of the infeasibilities in a model. If the control MAXIIS is set to a positive integer value then the problem.IISAll function will stop if MAXIIS IISs have been found. By default the control MAXIIS is set to -1, in which case an IIS is found for each of the infeasibilities in the model.
2. The problem attribute NUMIIS allows the user to recover the number of IISs found in a particular search. Alternatively, the problem.IISStatus function may be used to retrieve the number of IISs found by the problem.firstIIS, problem.nextIIS, or problem.IISAll functions.
Related topics
problem.getIISData, problem.clearIIS, problem.firstIIS, problem.IISIsolations, problem.nextIIS, problem.IISStatus, problem.writeIIS, problem.IISAll.
Parent Topic Deprecated functionality

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