Xpress problem methods

problem.addcbafterobjective	Declares a callback which will be called after each objective in a multi-objective problem is solved. This callback function will be called in addition to any callbacks already added by addcbafterobjective.
problem.addcbbariteration	Declares a barrier iteration callback function, called after each iteration during the interior point algorithm, with the ability to access the current barrier solution/slack/duals or reduced cost values, and to ask barrier to stop. This callback function will be called in addition to any callbacks already added by addcbbariteration.
problem.addcbbarlog	Declares a barrier log callback function, called at each iteration during the interior point algorithm. This callback function will be called in addition to any barrier log callbacks already added by addcbbarlog.
problem.addcbbeforeobjective	Declares a callback which will be called before each objective in a multi-objective problem is solved. This callback function will be called in addition to any callbacks already added by addcbbeforeobjective.
problem.addcbchecktime	Declares a callback function which is called every time the Optimizer checks if the time limit has been reached. This callback function will be called in addition to any callbacks already added by addcbchecktime.
problem.addcbchgbranchobject	Declares a callback function that will be called every time the Optimizer has selected a MIP entity for branching. Allows the user to inspect and override the Optimizer's branching choice. This callback function will be called in addition to any callbacks already added by problem.addcbchgbranchobject.
problem.addcbcutlog	Declares a cut log callback function, called each time the cut log is printed. This callback function will be called in addition to any callbacks already added by problem.addcbcutlog.
problem.addcbdestroymt	Declares a callback function that is called every time a MIP thread is destroyed by the parallel MIP code. This callback function will be called in addition to any callbacks already added by addcbdestroymt.
problem.addcbgapnotify	Declares a gap notification callback, to be called when a MIP solve reaches a predefined target, set using the miprelgapnotify, mipabsgapnotify, mipabsgapnotifyobj, and/or mipabsgapnotifybound controls.
problem.addcbinfnode	Declares a user infeasible node callback function, called after the current node has been found to be infeasible during the Branch and Bound search. This callback function will be called in addition to any callbacks already added by addcbinfnode.
problem.addcbintsol	Declares a user integer solution callback function, called every time an integer solution is found by heuristics or during the Branch and Bound search. This callback function will be called in addition to any callbacks already added by addcbintsol.
problem.addcblplog	Declares a simplex log callback function which is called after every LPLOG iterations of the simplex algorithm. This callback function will be called in addition to any callbacks already added by addcblplog.
problem.addcbmessage	Declares an output callback function, called every time a text line relating to the given prob is output by the Optimizer. This callback function will be called in addition to any callbacks already added by addcbmessage.
problem.addcbmiplog	Declares a MIP log callback function, called each time the MIP log is printed. This callback function will be called in addition to any callbacks already added by addcbmiplog.
problem.addcbmipthread	Declares a MIP thread callback function, called every time a MIP worker problem is created by the parallel MIP code. This callback function will be called in addition to any callbacks already added by addcbmipthread.
problem.addcbnewnode	Declares a callback function that will be called every time a new node is created during the branch and bound search. This callback function will be called in addition to any callbacks already added by addcbnewnode.
problem.addcbnodecutoff	Declares a user node cutoff callback function, called every time a node is cut off as a result of an improved integer solution being found during the branch and bound search. This callback function will be called in addition to any callbacks already added by addcbnodecutoff.
problem.addcbnodelpsolved	Declares a node LP solved callback function, called during the branch and bound search, after the LP relaxation has been solved for the current node, but before any internal cuts and heuristics have been applied. This callback function will be called in addition to any callbacks already added by XPRSaddcbnodelpsolved.
problem.addcboptnode	Declares an optimal node callback function, called during the branch and bound search, after the LP relaxation has been solved for the current node, and after any internal cuts and heuristics have been applied, but before the Optimizer checks if the current node should be branched. This callback function will be called in addition to any callbacks already added by addcboptnode.
problem.addcbpreintsol	Declares a user integer solution callback function, called when an integer solution is found by heuristics or during the branch and bound search, but before it is accepted by the Optimizer. This callback function will be called in addition to any integer solution callbacks already added by addcbpreintsol.
problem.addcbprenode	Declares a preprocess node callback function, called before the LP relaxation of a node has been optimized, so the solution at the node will not be available. This callback function will be called in addition to any callbacks already added by addcbprenode.
problem.addcbusersolnotify	Declares a callback function to be called each time a solution added by problem.addmipsol has been processed. This callback function will be called in addition to any callbacks already added by addcbusersolnotify.
problem.addcoefs	Add non-linear coefficients to the SLP problem
problem.addcols	Add columns to the problem after passing it to the Optimizer using the input routines.
problem.addConstraint	Adds one or more constraints to the problem.
problem.addcuts	Adds cuts directly to the matrix at the current node. Any cuts added to the matrix at the current node and not deleted at the current node will be automatically added to the cut pool. The cuts added to the cut pool will be automatically restored at descendant nodes.
problem.adddfs	Add a set of distribution factors
problem.addgencons	Adds one or more general constraints to the problem. Each general constraint y = f(x1, ..., xn, c1, ..., cn) consists of one or more (input) columns xi, zero or more constant values ci and a resultant (output column) y. General constraints can be defined using operators such as maximum and minimum (at least one input column of any contype and arbitrary number of input values), and and or (at least one binary input column, no constant values, binary resultant) and absolute value (exactly one input column of arbitrary contype, no constant values).
problem.addIndicator	Adds one or more indicator constraints to the problem.
problem.addmipsol	Adds a new feasible, infeasible or partial MIP solution for the problem to the Optimizer.
problem.addnames	Associates names with rows, columns, sets, piecewise linear constraints, general constraints or objectives.
problem.addobj	Appends an objective function with the given coefficients to a multi-objective problem. The weight and priority of the objective are set to the given values.
problem.addObjective	Adds one or more objective functions to the problem.
problem.addpwlcons	Adds one or more piecewise linear constraints to the problem. Each piecewise linear constraint y = f(x) consists of an (input) column x, a resultant (output column) y and a piecewise linear function f. The piecewise linear function f is described by a number of breakpoints, which are given as combinations of x- and y-values. Discontinuous piecewise linear functions are supported, in this case both the left and right limit at a given point need to be entered as breakpoints. To differentiate between left and right limit, the breakpoints need to be given as a list with non-decreasing x-values.
problem.addqmatrix	Adds a new quadratic matrix into a row defined by triplets.
problem.addrows	Adds rows and their coefficient to the problem.
problem.addsetnames	When a model with MIP entities is loaded, any special ordered sets may not have names associated with them. If you wish names to appear in the ASCII solutions files, the names for a range of sets can be added with this function.
problem.addSOS	Creates a special ordered set (SOS) constraint within the problem.
problem.addtolsets	Add sets of standard tolerance values to an SLP problem
problem.addVariable	Creates a variable within the problem.
problem.addVariables	Creates a dictionary or NumPy array of variables and adds them to the problem. Similar to the creation of a single variable with problem.addVariable, addVariables allows for using one or more index sets, specified as sets, lists, range objects, or any iterable object. Specifying a number k as an argument is equivalent to range(k) but can be used to create NumPy multiarrays of variables, and allows for more efficient creation. The result is otherwise a Python dictionary of variables, whose keys are tuple of indices. A collection of variables x that is created with addVariables can be indexed, for instance, as x[i,j] where i and j are indices in the lists provided.
problem.addvars	Add SLP variables defined as matrix columns to an SLP problem
problem.basisstability	Returns various measures for the stability of the current basis, including the basis condition number.
problem.bndsa	Returns upper and lower sensitivity ranges for specified variables' lower and upper bounds. If the bounds are varied within these ranges the current basis remains optimal and feasible.
problem.btran	Post-multiplies a (row) vector provided by the user by the inverse of the current basis.
problem.calcobjective	Returns the objective value of a given solution.
problem.calcobjn	Returns the value of a given objective. A solution can optionally be provided, otherwise the current solution will be used.
problem.calcreducedcosts	Returns the reduced cost values for a given (row) dual solution.
problem.calcslacks	Calculates the row slack values for a given solution.
problem.calcsolinfo	Returns the required property of a solution, like maximum infeasibility of a given primal and duals solution.
problem.cascade	Re-calculate consistent values for SLP variables. based on the current values of the remaining variables
problem.cascadeorder	Establish a re-calculation sequence for SLP variables with determining rows.
problem.chgbounds	Changes the bounds on columns in the problem.
problem.chgcascadenlimit	Set a variable specific cascade iteration limit
problem.chgccoef	Add or change a single matrix coefficient using a string for the formula
problem.chgcoef	Changes a single coefficient in the problem. If the coefficient does not already exist, a new coefficient will be added to the problem. If many coefficients are being added to a row of the problem, it may be more efficient to delete the old row and add a new row.
problem.chgcoltype	Changes the type of a column in the problem.
problem.chgdeltatype	Changes the type of the delta assigned to a nonlinear variable
problem.chgdf	Set or change a distribution factor
problem.chgglblimit	Changes semi-continuous or semi-integer lower bounds, or upper limits on partial integers.
problem.chgmcoef	Change multiple coefficients in the problem. The coefficients that do not exist yet will be added to the problem. If many coefficients are being added to a row of the matrix, it may be more efficient to delete the old row of the matrix and add a new one.
problem.chgmqobj	Change multiple quadratic coefficients in the objective function. If any of the coefficients does not exist already, new coefficients will be added to the objective function.
problem.chgnlcoef	Add or change a single matrix coefficient using a parsed or unparsed formula
problem.chgobj	Change the objective function coefficients.
problem.chgobjn	Modifies one or more coefficients of an objective function in a multi-objective problem. If the objective already exists, any coefficients not present in the colind and objcoef arrays will unchanged. If the objective does not exist, it will be added to the problem.
problem.chgobjsense	Changes the problem's objective function objsense to minimize or maximize.
problem.chgqobj	Change a single quadratic coefficient in the objective function corresponding to the variable pair (objqcol1,objqcol2) of the Hessian matrix.
problem.chgqrowcoeff	Changes a single quadratic coefficient in a row.
problem.chgrhs	Changes righthand side values of the problem.
problem.chgrhsrange	Change the range for one or more rows of the problem.
problem.chgrowstatus	Change the status setting of a constraint
problem.chgrowtype	Changes the type of a row in the problem.
problem.chgrowwt	Set or change the initial penalty error weight for a row
problem.chgtolset	Add or change a set of convergence tolerances used for SLP variables
problem.chgvar	Define a column as an SLP variable or change the characteristics and values of an existing SLP variable
problem.construct	Create the full augmented SLP matrix and data structures, ready for optimization
problem.copy	Obtains a copy of a problem.
problem.copycallbacks	Copies callback functions defined for one problem to another.
problem.copycontrols	Copies controls defined for one problem to another.
problem.crossoverlpsol	Provides a basic optimal solution for a given solution of an LP problem. This function behaves like the crossover after the barrier algorithm.
problem.delcoefs	Delete coefficients from the current problem
problem.delConstraint	Delete one or more constraints from the problem.
problem.delcpcuts	During the branch and bound search, cuts are stored in the cut pool to be applied at descendant nodes. These cuts may be removed from a given node using problem.delcuts, but if this is to be applied in a large number of cases, it may be preferable to remove the cut completely from the cut pool. This is achieved using delcpcuts.
problem.delcuts	Deletes cuts from the matrix at the current node. Cuts from the parent node which have been automatically restored may be deleted as well as cuts added to the current node using problem.addcuts or problem.loadcuts. The cuts to be deleted can be specified in a number of ways. If a cut is ruled out by any one of the criteria it will not be deleted.
problem.delgencons	Delete general constraints from a problem.
problem.delindicators	Delete indicator constraints. This turns the specified rows into normal rows (not controlled by indicator variables).
problem.delobj	Removes an objective function from a multi-objective problem. Any objectives with index > objidx will be shifted down. Deleting the last objective function in the problem causes all the objective coefficients to be zeroed, but OBJECTIVES remains set to 1.
problem.delpwlcons	Delete piecewise linear constraints from a problem.
problem.delqmatrix	Deletes the quadratic part of a row or of the objective function.
problem.delSOS	Delete one or more SOSs from the problem.
problem.deltolsets	Delete tolerance sets from the current problem
problem.delVariable	Delete one or more variables from the problem.
problem.delvars	Convert SLP variables to normal columns. Variables must not appear in SLP structures
problem.dumpcontrols	Displays the list of controls and their current value for those controls that have been set to a non default value.
problem.estimaterowdualranges	Performs a dual side range sensitivity analysis, i.e. calculates estimates for the possible ranges for dual values.
problem.evaluatecoef	Evaluate a coefficient using the current values of the variables
problem.evaluateformula	Evaluate a formula using the current values of the variables
problem.fixmipentities	Fixes all the MIP entities to the values of the last found MIP solution. This is useful for finding the reduced costs for the continuous variables after the MIP entities have been fixed to their optimal values.
problem.fixpenalties	Fixe the values of the error vectors
problem.ftran	Pre-multiplies a (column) vector provided by the user by the inverse of the current matrix.
problem.getAttrib	Retrieves one or more attributes of a problem.
problem.getattribinfo	Accesses the id number and the type information of an attribute given its name. An attribute name may be for example 'rows'. The function will return an id number of 0 and a type value of notdefined if the name is not recognized as an attribute name. Note that this will occur if the name is a control name and not an attribute name.
problem.getbasis	Returns the current basis into the user's data arrays.
problem.getbasisval	Returns the current basis status for a specific col or row.
problem.getCallbackDuals	Used to obtain the dual values from the solution associated with the current callback.
problem.getCallbackPresolveDuals	Returns the dual values from the solution to the presolved problem associated with the current callback.
problem.getCallbackPresolveRedcosts	Returns the reduced costs from the solution to the presolved problem associated with the current callback.
problem.getCallbackPresolveSlacks	Returns the slack values from the solution to the presolved problem associated with the current callback.
problem.getCallbackPresolveSolution	Returns the solution to the presolved problem associated with the current callback.
problem.getCallbackRedCosts	Used to obtain the reduced costs from the solution associated with the current callback.
problem.getCallbackSlacks	Used to obtain the slack values from the solution associated with the current callback.
problem.getCallbackSolution	Used to obtain the solution associated with the current callback.
problem.getccoef	Retrieve a single nonlinear matrix coefficient as a formula in a string.
problem.getcoef	Returns a single coefficient in the constraint matrix.
problem.getcoefformula	Retrieve a single nonlinear matrix coefficient as a formula split into tokens
problem.getcoefs	Retrieve the list of positions of the nonlinear coefficients in the problem
problem.getcolinfo	Get current column information.
problem.getcols	Returns the nonzeros in the constraint matrix for the columns in a given range.
problem.getcoltype	Returns the column types for the columns in a given range.
problem.getConstraint	Returns one or more constraint of a problem corresponding to one or more indices passed as arguments. These constraints are returned as Python objects and can be used to access and manipulate the problem.
problem.getControl	Retrieves one or more controls of a problem. Can also be used to retrieve objective controls.
problem.getcontrolinfo	Accesses the id number and the type information of a control given its name. A control name may be for example 'presolve'. The function will return an id number of 0 and a type value of notdefined if the name is not recognized as a control name. Note that this will occur if the name is an attribute name rather than a control name.
problem.getcpcutlist	Returns a list of cut indices from the cut pool.
problem.getcpcuts	Returns cuts from the cut pool. A list of cuts in the array mindex must be passed to the routine. The columns and elements of the cut will be returned in the regions pointed to by the colind and cutcoef parameters. The columns and elements will be stored contiguously and the starting point of each cut will be returned in the region pointed to by the start parameter.
problem.getcutlist	Retrieves a list of cuts for the cuts active at the current node.
problem.getcutmap	Returns in which rows a list of cutind are currently loaded into the Optimizer. This is useful for example to retrieve the duals associated with active cutind.
problem.getcutslack	Used to calculate the slack value of a cutind with respect to the current LP relaxation solution. The slack is calculated from the cutind itself, and might be requested for any cutind (even if it is not currently loaded into the problem).
problem.getdf	Get a distribution factor
problem.getdirs	Returns the directives that have been loaded into a problem. Priorities, forced branching directions and pseudo costs can be returned. If called after presolve, getdirs will get the directives for the presolved problem.
problem.getDual
problem.getdualray	Retrieves a dual ray (dual unbounded direction) for the current problem, if the problem is found to be infeasible.
problem.getDuals	Used to obtain the dual values associated with the incumbent solution during or after optimization with problem.optimize, problem.mipoptimize, problem.lpoptimize or problem.nlpoptimize.
problem.getgencons	Returns the general constraints y = f(x1, ..., xn, c1, ..., cm) in a given range.
problem.getiisdata	Returns information for an Irreducible Infeasible Set: size, variables (row and column vectors) and conflicting sides of the variables, duals and reduced costs.
problem.getIndex	Returns the numerical index for a specified row, column, or set of the optimizer.
problem.getIndexFromName	Returns the index for a specified row or column name.
problem.getindicators	Returns the indicator constraint condition (indicator variable and complement flag) associated to the rows in a given range.
problem.getinfeas	Returns a list of infeasible primal and dual variables.
problem.getlastbarsol	Obtains the last barrier solution values following optimization that used the barrier solver.
problem.getlasterror	Returns the error message corresponding to the last error triggered by a library function.
problem.getlb	Returns the lower bounds on the columns in a given range.
problem.getlpsol	Used to obtain the LP solution values following optimization.
problem.getlpsolval	Used to obtain a single LP solution value following optimization.
problem.getmessagestatus	Returns the current suppression status of a message: nonzero if the message is not suppressed; 0 otherwise.
problem.getmipentities	Retrieves MIP entity information about a problem. It must be called before problem.mipoptimize if the presolve option is used.
problem.getmipsol	Used to obtain the solution values of the last MIP solution that was found.
problem.getmipsolval	Used to obtain a single solution value of the last MIP solution that was found.
problem.getmqobj	Returns the nonzeros in the quadratic objective coefficients' matrix for the columns in a given range. To achieve maximum efficiency, getmqobj returns the lower triangular part of this matrix only.
problem.getnamelist	Returns the names for the rows, columns, sets, piecewise linear constraints, general constraints or objectives in a given range. The names will be returned in a list of Python strings.
problem.getobj	Returns the objective function coefficients for the columns in a given range.
problem.getobjn	Returns the coefficients of a given objective function for the columns in a given range.
problem.getObjVal	Returns the objective value of the solution found by the Optimizer.
problem.getOutputEnabled	Returns True if Optimizer messages will be written to the Python output stream, False otherwise.
problem.getpivotorder	Returns the pivot order of the basic variables.
problem.getpivots	Returns a list of potential leaving variables if a specified variable enters the basis. The return value is a tuple containing the objective function value that would result if enter entered the basis; and an integer where the actual number of potential leaving variables will be returned.
problem.getpresolvebasis	Returns the current basis from memory into the user's data areas. If the problem is presolved, the presolved basis will be returned. Otherwise the original basis will be returned.
problem.getpresolvemap	Returns the mapping of the row and column numbers from the presolve problem back to the original problem.
problem.getpresolvesol	Returns the solution for the presolved problem from memory.
problem.getprimalray	Retrieves a primal ray (primal unbounded direction) for the current problem, if the problem is found to be unbounded.
problem.getProbStatus	Returns the problem status before or after a call to problem.optimize.
problem.getProbStatusString	Returns the string corresponding to the problem status before or after a call to problem.optimize.
problem.getpwlcons	Returns the piecewise linear constraints y = f(x) in a given range.
problem.getqobj	Returns a single quadratic objective function coefficient corresponding to the variable pair (objqcol1, objqcol2) of the Hessian matrix.
problem.getqrowcoeff	Returns a single quadratic constraint coefficient corresponding to the variable pair (rowqcol1, rowqcol2) of the Hessian of a given constraint.
problem.getqrowqmatrix	Returns the nonzeros in a quadratic constraint coefficients matrix for the columns in a given range. To achieve maximum efficiency, getqrowqmatrix returns the lower triangular part of this matrix only.
problem.getqrowqmatrixtriplets	Returns the nonzeros in a quadratic constraint coefficients matrix as triplets (index pairs with coefficients). To achieve maximum efficiency, getqrowqmatrixtriplets returns the lower triangular part of this matrix only.
problem.getqrows	Returns a list of row objects that have quadratic coefficients.
problem.getRCost
problem.getRedCosts	Used to obtain the reduced costs associated with the incumbent solution during or after optimization with problem.optimize, problem.mipoptimize, problem.lpoptimize or problem.nlpoptimize.
problem.getrhs	Returns the right hand side elements for the rows in a given range.
problem.getrhsrange	Returns the right hand side range values for the rows in a given range.
problem.getrowinfo	Get current row information.
problem.getrows	Returns the nonzeros in the constraint matrix for the rows in a given range.
problem.getrowstatus	Retrieve the status setting of a constraint
problem.getrowtype	Returns the row types for the rows in a given range.
problem.getrowwt	Get the initial penalty error weight for a row
problem.getscaledinfeas	Returns a list of scaled infeasible primal and dual variables for the original problem. If the problem is currently presolved, it is postsolved before the function returns.
problem.getSlack
problem.getSlacks	Used to obtain the slack values associated with the incumbent solution during or after optimization with problem.optimize, problem.mipoptimize, problem.lpoptimize or problem.nlpoptimize.
problem.getslpsol	Obtain the solution values for the most recent SLP iteration
problem.getSolution	Used to obtain the incumbent solution during or after optimization with problem.optimize, problem.mipoptimize, problem.lpoptimize or problem.nlpoptimize.
problem.getSOS	Returns one or more SOSs of a problem corresponding to one or more indices passed as arguments. These SOSs are returned as Python objects and can be used to access and manipulate the problem.
problem.gettolset	Retrieve the values of a set of convergence tolerances for an SLP problem
problem.getub	Returns the upper bounds on the columns in a given range.
problem.getunbvec	Returns the index vector which causes the primal simplex or dual simplex algorithm to determine that a problem is primal or dual unbounded respectively.
problem.getvar	Retrieve information about an SLP variable
problem.getVariable	Returns one or more variables of a problem corresponding to one or more indices passed as arguments. These variables are returned as Python objects and can be used to access and manipulate the problem.
problem.hasdualray	Returns true if a dual ray (dual unbounded direction) exists for the current problem, if the problem is found to be infeasible.
problem.hasprimalray	Returns true if a primal ray (primal unbounded direction) exists for the current problem, if the problem is found to be unbounded.
problem.iisall	Performs an automated search for independent Irreducible Infeasible Sets (IIS) in an infeasible problem.
problem.iisclear	Resets the search for Irreducible Infeasible Sets (IIS).
problem.iisfirst	Initiates a search for an Irreducible Infeasible Set (IIS) in an infeasible problem. The returned value can be 0 for success, 1 if the problem is feasible, or 2 in case of error.
problem.iisisolations	Performs the isolation identification procedure for an Irreducible Infeasible Set (IIS).
problem.iisnext	Continues the search for further Irreducible Infeasible Sets (IIS), or calls problem.iisfirst if no IIS has been identified yet. The returned value is 0 in case of success; 1 if no more IIS could be found, or problem is feasible if no problem.iisfirst call preceded; or 2 in case of an error.
problem.iisstatus	Returns statistics on the Irreducible Infeasible Sets (IIS) found so far by problem.iisfirst, problem.iisnext, or problem.iisall. The returned value is the number of IISs found so far.
problem.iiswrite	Writes an LP/MPS/CSV file containing a given Irreducible Infeasible Set (IIS). If 0 is passed as the IIS number parameter, the initial infeasible subproblem is written.
problem.interrupt	Interrupts the Optimizer algorithms.
problem.loadbasis	Loads a basis as specified by the user.
problem.loadbranchdirs	Loads directives into the current problem to specify which MIP entities the Optimizer should continue to branch on when a node solution is integer feasible.
problem.loadcoefs	Load non-linear coefficients into the SLP problem
problem.loadcuts	Loads cuts from the cut pool into the matrix. Without calling loadcuts the cuts will remain in the cut pool but will not be active at the node. Cuts loaded at a node remain active at all descendant nodes unless they are deleted using problem.delcuts.
problem.loaddelayedrows	Specifies that a set of rows in the problem will be treated as delayed rows during a tree search. These are rows that must be satisfied for any integer solution, but will not be loaded into the active set of constraints until required.
problem.loaddfs	Load a set of distribution factors
problem.loaddirs	Loads directives into the problem.
problem.loadlpsol	Loads an LP solution for the problem into the Optimizer. The returned status is either 0 if the solution is loaded or 1 if the solution is not loaded because the problem is in presolved status.
problem.loadmipsol	Loads a MIP solution for the problem into the Optimizer. The returned status is one of the following values: -1: Solution rejected because an error occurred; 0: Solution accepted. When loading a solution before a MIP solve, the solution is always accepted. See Further Information below. 1: Solution rejected because it is infeasible; 2: Solution rejected because it is cut off; 3: Solution rejected because the LP reoptimization was interrupted.
problem.loadmodelcuts	Specifies that a set of rows in the problem will be treated as model cuts.
problem.loadpresolvebasis	Loads a presolved basis from the user's areas.
problem.loadpresolvedirs	Loads directives into the presolved matrix.
problem.loadproblem	Load an optimization problem, possibly with quadratic objective and/or constraints, and integer variables.
problem.loadsecurevecs	Allows the user to mark rows and columns in order to prevent the presolve removing these rows and columns from the problem.
problem.loadtolsets	Load sets of standard tolerance values into an SLP problem
problem.loadvars	Load SLP variables defined as matrix columns into an SLP problem
problem.lpoptimize	This function begins a search for the optimal continuous (LP) solution. The direction of optimization is given by OBJSENSE. The status of the problem when the function completes can be checked using LPSTATUS. Any MIP entities in the problem will be ignored.
problem.mipoptimize	This function begins a tree search for the optimal MIP solution. The direction of optimization is given by OBJSENSE. The status of the problem when the function completes can be checked using MIPSTATUS.
problem.msaddcustompreset	A combined version of msaddjob and msaddpreset. The preset described is loaded, topped up with the specific settings supplied
problem.msaddjob	Adds a multistart job to the multistart pool
problem.msaddpreset	Loads a preset of jobs into the multistart job pool.
problem.msclear	Removes all scheduled jobs from the multistart job pool
problem.name	Returns the name of the problem as a Python string.
problem.nlpchgformula	Add or replace a single matrix formula using a parsed or unparsed formula
problem.nlpchgformulastr	Add or replace a single matrix formula using a character string for the formula.
problem.nlpgetformula	Retrieve a single matrix formula split into tokens
problem.nlpgetformulastr	Retrieve a single matrix formula in a character string
problem.nlpoptimize	Solves an SLP problem
problem.nlpsetinitval	Set the initial value of a nonlinear variable
problem.objsa	Returns upper and lower sensitivity ranges for specified objective function coefficients. If the objective coefficients are varied within these ranges the current basis remains optimal and the reduced costs remain valid.
problem.optimize	This function begins a search for the optimal solution of the problem. The direction of optimization is given by OBJSENSE.
problem.postsolve	Postsolve the current problem when it is in a presolved state.
problem.presolve	Perform a nonlinear presolve on the problem
problem.presolverow	Presolves a row formulated in terms of the original variables such that it can be added to a presolved problem. Returns a tuple of two elements containing, respectively, the presolved right-hand side and the status of the presolved row: -3: Failed to presolve the row due to presolve dual reductions; -2: Failed to presolve the row due to presolve duplicate column reductions; -1: Failed to presolve the row due to an error. Check the Optimizer error code for the cause; 0: The row was successfully presolved; 1: The row was presolved, but may be relaxed.
problem.printevalinfo	Print a summary of any evaluation errors that may have occurred during solving a problem
problem.printmemory	Print the dimensions and memory allocations for a problem
problem.read	Read an optimization problem into a Python problem object created prior to the call. All formats allowed by the Xpress Optimizer C API are allowed.
problem.readbasis	Instructs the Optimizer to read in a previously saved basis from a file.
problem.readbinsol	Reads a solution from a binary solution file.
problem.readdirs	Reads a directives file to help direct the tree search.
problem.readslxsol	Reads an ASCII solution file .slx created by the problem.writeslxsol function.
problem.refinemipsol	Runs the MIP solution refiner.
problem.reinitialize	Reset the SLP problem to match a just augmented system
problem.removecbafterobjective	Removes a user after objective callback function previously added by addcbafterobjective. The specified callback function will no longer be called after it has been removed.
problem.removecbbariteration	Removes a barrier iteration callback function previously added by addcbbariteration. The specified callback function will no longer be called after it has been removed.
problem.removecbbarlog	Removes a newton barrier log callback function previously added by addcbbarlog. The specified callback function will no longer be called after it has been removed.
problem.removecbbeforeobjective	Removes a user before objective callback function previously added by addcbbeforeobjective. The specified callback function will no longer be called after it has been removed.
problem.removecbchecktime	Removes a callback function previously added by problem.addcbchecktime. The specified callback function will no longer be called after it has been removed.
problem.removecbchgbranchobject	Removes a callback function previously added by addcbchgbranchobject. The specified callback function will no longer be called after it has been removed.
problem.removecbcutlog	Removes a cut log callback function previously added by addcbcutlog. The specified callback function will no longer be called after it has been removed.
problem.removecbdestroymt	Removes a slave thread destruction callback function previously added by addcbdestroymt. The specified callback function will no longer be called after it has been removed.
problem.removecbgapnotify	Removes a callback function previously added by problem.addcbgapnotify. The specified callback function will no longer be removed after it has been returned.
problem.removecbinfnode	Removes a user infeasible node callback function previously added by addcbinfnode. The specified callback function will no longer be called after it has been removed.
problem.removecbintsol	Removes an integer solution callback function previously added by addcbintsol. The specified callback function will no longer be called after it has been removed.
problem.removecblplog	Removes a simplex log callback function previously added by addcblplog. The specified callback function will no longer be called after it has been removed.
problem.removecbmessage	Removes a message callback function previously added by addcbmessage. The specified callback function will no longer be called after it has been removed.
problem.removecbmiplog	Removes a MIP log callback function previously added by addcbmiplog. The specified callback function will no longer be called after it has been removed.
problem.removecbmipthread	Removes a callback function previously added by addcbmipthread. The specified callback function will no longer be called after it has been removed.
problem.removecbnewnode	Removes a new-node callback function previously added by addcbnewnode. The specified callback function will no longer be called after it has been removed.
problem.removecbnodecutoff	Removes a node-cutoff callback function previously added by addcbnodecutoff. The specified callback function will no longer be called after it has been removed.
problem.removecbnodelpsolved	Removes a node lp solved callback function previously added by addcbnodelpsolved. The specified callback function will no longer be called after it has been removed.
problem.removecboptnode	Removes a node-optimal callback function previously added by addcboptnode. The specified callback function will no longer be called after it has been removed.
problem.removecbpreintsol	Removes a pre-integer solution callback function previously added by addcbpreintsol. The specified callback function will no longer be called after it has been removed.
problem.removecbprenode	Removes a preprocess node callback function previously added by addcbprenode. The specified callback function will no longer be called after it has been removed.
problem.removecbusersolnotify	Removes a user solution notification callback previously added by problem.addcbusersolnotify. The specified callback function will no longer be called after it has been removed.
problem.repairinfeas	Provides a simplified interface for problem.repairweightedinfeas. The returned value is as follows: 0: relaxed optimum found; 1: relaxed problem is infeasible; 2: relaxed problem is unbounded; 3: solution of the relaxed problem regarding the original objective is nonoptimal; 4: error (when return code is nonzero); 5: numerical instability; 6: analysis of an infeasible relaxation was performed, but the relaxation is feasible.
problem.repairweightedinfeas	By relaxing a set of selected constraints and bounds of an infeasible problem, it attempts to identify a 'solution' that violates the selected set of constraints and bounds minimally, while satisfying all other constraints and bounds. Among such solution candidates, it selects one that is optimal regarding to the original objective function. Similar to repairinfeas, the returned value is as follows: 1: relaxed problem is infeasible; 2: relaxed problem is unbounded; 3: solution of the relaxed problem regarding the original objective is nonoptimal; 4: error (when return code is nonzero); 5: numerical instability; 6: analysis of an infeasible relaxation was performed, but the relaxation is feasible.
problem.repairweightedinfeasbounds	An extended version of problem.repairweightedinfeas that allows for bounding the level of relaxation allowed. The returned value is the same as repairweightedinfeas.
problem.reset	Clears all information regarding an optimization problem and returns it to the same status as it would be after creation (i.e. after the instruction p = xpress.problem()).
problem.restore	Restores the Optimizer's data structures from a file created by problem.save. Optimization may then recommence from the point at which the file was created.
problem.rhssa	Returns upper and lower sensitivity ranges for specified right hand side (RHS) function coefficients. If the RHS coefficients are varied within these ranges the current basis remains optimal and the reduced costs remain valid.
problem.save	Saves the current data structures, i.e. matrices, control settings and problem attribute settings to file and terminates the run so that optimization can be resumed later.
problem.scale	Re-scales the current problem.
problem.scaling	Analyze the current matrix for largest/smallest coefficients and ratios
problem.setcbcascadeend	Set a user callback to be called at the end of the cascading process, after the last variable has been cascaded
problem.setcbcascadestart	Set a user callback to be called at the start of the cascading process, before any variables have been cascaded
problem.setcbcascadevar	Set a user callback to be called after each column has been cascaded
problem.setcbcascadevarfail	Set a user callback to be called after cascading a column was not successful
problem.setcbcoefevalerror	Set a user callback to be called when an evaluation of a coefficient fails during the solve
problem.setcbconstruct	Set a user callback to be called during the Xpress SLP augmentation process
problem.setcbdestroy	Set a user callback to be called when an SLP problem is about to be destroyed
problem.setcbdrcol	Set a user callback used to override the update of variables with small determining column
problem.setcbintsol	Set a user callback to be called during MISLP when an integer solution is obtained
problem.setcbiterend	Set a user callback to be called at the end of each SLP iteration
problem.setcbiterstart	Set a user callback to be called at the start of each SLP iteration
problem.setcbitervar	Set a user callback to be called after each column has been tested for convergence
problem.setcbmessage	Set a user callback to be called whenever Xpress Nonlinear outputs a line of text
problem.setcbmsjobend	Set a user callback to be called every time a new multistart job finishes. Can be used to overwrite the default solution ranking function
problem.setcbmsjobstart	Set a user callback to be called every time a new multistart job is created, and the pre-loaded settings are applied
problem.setcbmswinner	Set a user callback to be called every time a new multistart job is created, and the pre-loaded settings are applied
problem.setcboptnode	Set a user callback to be called during MISLP when an optimal SLP solution is obtained at a node
problem.setcbprenode	Set a user callback to be called during MISLP after the set-up of the SLP problem to be solved at a node, but before SLP optimization
problem.setcbpreupdatelinearization	Set a user callback to be called before the linearization is updated
problem.setcbslpend	Set a user callback to be called at the end of the SLP optimization
problem.setcbslpnode	Set a user callback to be called during MISLP after the SLP optimization at each node.
problem.setcbslpstart	Set a user callback to be called at the start of the SLP optimization
problem.setControl	Sets one or more controls of a problem. Can also be used to set objective controls.
problem.setcurrentiv	Transfer the current solution to initial values
problem.setdefaultcontrol	Sets one control to its default values. Must be called before the problem is read or loaded by problem.read and problem.loadproblem.
problem.setdefaults	Sets all controls to their default values. It must be called before the problem is read with problem.read or loaded with problem.loadproblem.
problem.setindicators	Specifies that a set of rows in the problem will be treated as indicator constraints during a tree search. An indicator constraint is made of a condition and a linear inequality. The condition is of the type "bin = value", where bin is a binary variable and value is either 0 or 1. The linear inequality is any linear row in the problem with type <= (L) or >= (G). During tree search, a row configured as an indicator constraint is enforced only when condition holds, that is only if the indicator variable bin has the specified value.
problem.setlogfile	This directs all Optimizer output to a log file.
problem.setmessagestatus	Manages suppression of messages.
problem.setObjective	Sets the objective function of the problem.
problem.setOutputEnabled	Enables or disables writing Optimizer messages to the Python output stream.
problem.setprobname	Sets the current default problem name.
problem.slpchgcoef	Add or change a single matrix coefficient using a parsed or unparsed formula
problem.slpchgcoefstr	Add or change a single matrix coefficient using a string for the formula
problem.slpgetcoefformula	Retrieve a single matrix formula split into tokens
problem.slpgetcoefstr	Retrieve a single matrix coefficient as a formula in a character string
problem.storecuts	Stores cuts into the cut pool, but does not apply them to the current node. These cuts must be explicitly loaded into the matrix using problem.loadcuts before they become active.
problem.strongbranch	Performs strong branching iterations on all specified bound changes. For each candidate bound change, strongbranch performs dual simplex iterations starting from the current optimal solution of the base LP, and returns both the status and objective value reached after these iterations.
problem.strongbranchcb	Performs strong branching iterations on all specified bound changes. For each candidate bound change, strongbranchcb performs dual simplex iterations starting from the current optimal solution of the base LP, and returns both the status and objective value reached after these iterations.
problem.tune	Begin a tuner session for the current problem. The tuner will solve the problem multiple times while evaluating a list of control settings and promising combinations of them. When finished, the tuner will select and set the best control setting on the problem. Note that the direction of optimization is given by xpress.attributes.objsense.
problem.tuneprobsetfile	This function begins a tuner session for a set of problems. The tuner will solve the problems multiple times while evaluating a list of control settings and promising combinations of them. When finished, the tuner will select and set the best control setting on the problems.
problem.tunerreadmethod	Load a user defined tuner method from the given file.
problem.tunerwritemethod	Writes the current tuner method to a given file or prints it to the console.
problem.unconstruct	Reset the SLP problem and removes the augmentation structures
problem.updatelinearization	Updates the current linearization
problem.validate	Validate the feasibility of constraints in a converged solution
problem.validatekkt	Validates the first order optimality conditions also known as the Karush-Kuhn-Tucker (KKT) conditions versus the currect solution
problem.validaterow	Prints an extensive analysis on a given constraint of the SLP problem
problem.validatevector	Validate the feasibility of constraints for a given solution
problem.write	Writes the current problem to an MPS or LP file.
problem.writebasis	Writes the current basis to a file for later input into the Optimizer.
problem.writebinsol	Writes the current MIP or LP solution to a binary solution file for later input into the Optimizer.
problem.writedirs	Writes the tree search directives from the current problem to a directives file.
problem.writeprtsol	Writes the current solution to a fixed format ASCII file, problem_name.prt.
problem.writeslxsol	Creates an ASCII solution file (.slx) using a similar format to MPS files. These files can be read back into the Optimizer using the problem.readslxsol function.
problem.writesol	Writes the current solution to a CSV format ASCII file, problem_name.asc(and .hdr).

© 2001-2025 Fair Isaac Corporation. All rights reserved. This documentation is the property of Fair Isaac Corporation (“FICO”). Receipt or possession of this documentation does not convey rights to disclose, reproduce, make derivative works, use, or allow others to use it except solely for internal evaluation purposes to determine whether to purchase a license to the software described in this documentation, or as otherwise set forth in a written software license agreement between you and FICO (or a FICO affiliate). Use of this documentation and the software described in it must conform strictly to the foregoing permitted uses, and no other use is permitted.

Contents

Index

Glossary

Search Results

Xpress problem methods