Error Codes

Errors can arise in most of the Gurobi library routines. In the C interface, library routines return an integer error code. In the C++, Java, .NET, and Python interfaces, Gurobi methods can throw an exception (a C++ exception, a Java exception, a .NET exception, or a Python exception).

Underlying all Gurobi error reporting is a set of error codes. These are integer values, but we recommend that you use one of the predefined error code constants to check the error status in your program. Each error code has a name, and each language requires a prefix on this name to obtain the appropriate constant. You would access error code OUT_OF_MEMORY in the following ways from the available Gurobi interfaces:

Language	Error Code
C	GRB_ERROR_OUT_OF_MEMORY
C++	GRB_ERROR_OUT_OF_MEMORY
Java	GRB.Error.OUT_OF_MEMORY
.NET	GRB.Error.OUT_OF_MEMORY
Python	GRB.Error.OUT_OF_MEMORY

Note that when an error occurs, it produces both an error code and an error message. The message can be obtained through GRBgeterrormessage in C, through GRBException::getMessage() in C++, through the inherited getMessage() method on the GRBException class in Java, through the inherited Message property on the GRBException class in .NET, or through the e.message attribute on the GurobiError object in Python.

In MATLAB and R, the error codes and corresponding messages are printed on the screen whenever an error occurs.

Possible error codes are:

Error code	Error number	Description
OUT_OF_MEMORY	10001	Available memory was exhausted
NULL_ARGUMENT	10002	NULL input value provided for a required argument
INVALID_ARGUMENT	10003	An invalid value was provided for a routine argument
UNKNOWN_ATTRIBUTE	10004	Tried to query or set an unknown attribute
DATA_NOT_AVAILABLE	10005	Attempted to query or set an attribute that could not be accessed at that time
INDEX_OUT_OF_RANGE	10006	Tried to query or set an attribute, but one or more of the provided indices (e.g., constraint index, variable index) was outside the range of valid values
UNKNOWN_PARAMETER	10007	Tried to query or set an unknown parameter
VALUE_OUT_OF_RANGE	10008	Tried to set a parameter to a value that is outside the parameter’s valid range
NO_LICENSE	10009	Failed to obtain a valid license
SIZE_LIMIT_EXCEEDED	10010	Attempted to solve a model that is larger than the limit for a demo license
CALLBACK	10011	Problem in callback
FILE_READ	10012	Failed to read the requested file
FILE_WRITE	10013	Failed to write the requested file
NUMERIC	10014	Numerical error during requested operation
IIS_NOT_INFEASIBLE	10015	Attempted to perform infeasibility analysis on a feasible model
NOT_FOR_MIP	10016	Requested operation not valid for a MIP model
OPTIMIZATION_IN_PROGRESS	10017	Tried to query or modify a model while optimization was in progress
DUPLICATES	10018	Constraint, variable, or SOS contained duplicated indices
NODEFILE	10019	Error in reading or writing a node file during MIP optimization
Q_NOT_PSD	10020	Q matrix in QP model is not positive semi-definite
QCP_EQUALITY_CONSTRAINT	10021	QCP equality constraint specified (only inequalities are supported if the NonConvex parameter is set to 0 or 1)
NETWORK	10022	Problem communicating with the Gurobi Compute Server
JOB_REJECTED	10023	Gurobi Compute Server responded, but was unable to process the job (typically because the queuing time exceeded the user-specified timeout or because the queue has exceeded its maximum capacity)
NOT_SUPPORTED	10024	Indicates that a Gurobi feature is not supported under your usage environment (for example, some advanced features are not supported in a Compute Server environment)
EXCEED_2B_NONZEROS	10025	Indicates that the user has called a query routine on a model with more than 2 billion non-zero entries, and the result would exceed the maximum size that can be returned by that query routine. The solution is typically to move to the GRBX version of that query routine, e.g. GRBXgetvars.
INVALID_PIECEWISE_OBJ	10026	Piecewise-linear objectives must have certain properties (as described in the documentation for the various setPWLObj methods). This error indicates that one of those properties was violated.
UPDATEMODE_CHANGE	10027	The UpdateMode parameter can not be modified once a model has been created.
CLOUD	10028	Problems launching a Gurobi Instant Cloud job.
MODEL_MODIFICATION	10029	Indicates that the user has modified the model in such a way that the model became invalid. For example, this happens when a general constraint exists in the model and the user deletes the resultant variable of this constraint. In such a case, the general constraint does not have any meaningful interpretation anymore. The solution is to also delete the general constraint when a resultant variable is deleted.
CSWORKER	10030	When you are using a client-server feature, this error indicates that there was an application problem.
TUNE_MODEL_TYPES	10031	Indicates that tuning was invoked on a set of models, but the models were of different types (e.g., one an LP, another a MIP).
SECURITY	10032	Indicates that an authentication step failed or that an operation was attempted for which the current credentials do not warrant permission.
NOT_IN_MODEL	20001	Tried to use a constraint or variable that is not in the model, either because it was removed or because it has not yet been added.
FAILED_TO_CREATE_MODEL	20002	Failed to create the requested model
INTERNAL	20003	Internal Gurobi error