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