User:Jcreer/MODFLOW 6 Changes for GMS 10.6: Difference between revisions

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*''Comments'' section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
*''Comments'' section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
*''Options'' section
*''Options'' section
**'''Auxiliary Variables...''' – Click to bring up the [[#Auxiliary Variables Dialog|''Auxiliary Variables'' dialog]].
**''AUXILIARY'' – Click the '''Auxiliary Variables...''' button to bring up the [[#Auxiliary Variables Dialog|''Auxiliary Variables'' dialog]].  
**'''Time Series...''' – Click to bring up the [[#Time Series Files Dialog|''Time Series Files'' dialog]].  
**''AUXMULTNAME'' – Auxiliary variable used as multiplier of CHD head value. Enter the name of auxiliary variable to be used as multiplier of CHD head value.
**'''Observations...''' – Click to bring up the [[#Observation Files Dialog|''Observation Files'' dialog]].  
**''AUXDEPTHNAME'' – Auxiliary variable defining depth at which drainage discharge will be scaled.
**''Use auxiliary variable as multiplier (AUXMULTNAME)'' – Name of auxiliary variable to be used as multiplier of drain conductance.
**''BOUNDNAMES'' – Allow boundary names. Turn on to allow boundary names to be included in the list of constant-head cells.
**''Allow boundary names (BOUNDNAMES)'' – Turn on to allow boundary names to be included in the list of drain cells.
**''PRINT_INPUT'' – Print input to listing file. Turn on to write the list of constant-head information to the listing file immediately after it is read.
**''Print input to listing file (PRINT_INPUT)'' – Turn on to write the list of drain information to the listing file immediately after it is read.
**''PRINT_FLOWS'' – Print flows to listing file. Turn on to write the list of constant-head flow rates to the listing file for every stress period time step in which "BUDGET PRINT" is specified in [[GMS:MF6 OC Package|Output Control]].
**''Print flows to listing file (PRINT_FLOWS)'' – Turn on to write the list of drain flow rates to the listing file for every stress period time step in which "BUDGET PRINT" is specified in [[GMS:MF6 OC Package|Output Control]].
**''TS6 FILEIN'' – Define time series files. Click the '''Files...''' button to bring up the [[#Time Series Files Dialog|''Time Series Files'' dialog]].
**''Save flows to budget file (SAVE_FLOWS)'' – Turn on to write  drain flow terms to the file specified with "BUDGET FILEOUT" in [[GMS:MF6 OC Package|Output Control]].
**''OBS6 FILEIN'' – Dfine observation files. Click teh '''Files...''' button to bring up the [[#Observation Files Dialog|''Observation Files'' dialog]].
**''Use with Water Mover (MVR) package (MOVER)'' – Turn on to allows this instance of the Drain Package to be used with the Water Mover (MVR) Package.
**''MOVER'' – Can be used with the Water Mover (MVR) package. Turn on to allows this instance of the Drain Package to be used with the Water Mover (MVR) Package.
 
*''Periods'' section – Contains the following:
*''Periods'' section – Contains the following:
**''Period'' drop-down – Use the '''Increment Up and Down''' [[File:Increment up and down arrows.png|14px]] buttons to select the desired period.
**''Period'' drop-down – Use the '''Increment Up and Down''' [[File:Increment up and down arrows.png|14px]] buttons to select the desired period.
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***Table – Contains the following:
***Table – Contains the following:
****''LAY'' – Used to specify which layer is being applied.
****''LAY'' – Used to specify which layer is being applied.
****''ROW'' – Used to specify which row is being applied.
****''CELL2D'' – Enter the cell ID that is being applied.
****''COL'' – Used to specify which column is being applied.
****''ELEV'' – Represents the elevation of the drain.
****''ELEV'' – Represents the elevation of the drain.
****''COND'' – Represents the hydraulic conductance between the aquifer and the drain.
****''COND'' – Represents the hydraulic conductance between the aquifer and the drain.

Revision as of 18:02, 13 August 2021

Gnome globe current event.png
 This contains information about functionality available starting at GMS version 10.6.
The content may not apply to other versions.
GMS Icon.png

Package Updates

TDIS

Gnome globe current event.png
 MODFLOW 6 is currently in Beta release for GMS
Some features and capabilities of MODFLOW 6 are still in development for GMS.
GMS Icon.png
MODFLOW 6
Models & Tools
GWF Model
GWT Model
Cell Properties Dialog
Zone File
Packages
Flow: GNC, HFB, NPF
GWF: BUY, CHD, CSUB,
DRN, EVT, GHB,
LAK, MAW, MVR,
OBS, RCH,RIV,
SFR, STO, UZF,
WEL
GWT: ADV, CNC, DSP
FMI, IC, IST, LKT,
MDT, MST, MVT,
MWT, OBS, SFT,
SRC,SSM, UZT
Other DIS, DISU, DISV,
IMS, OC, TDIS,
PEST
v • e

The Temporal Discretization (TDIS) Package dialog

The Temporal Discretization (TDIS) Package dialog is accessed by double-clicking on the TDIS package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

  • Sections list – A list of sections that can be turned on or off:
    • Comments – Turn on to make the Comments section visible.
    • Options – Turn on to make the Options section visible.
    • PeriodData – Turn on to make the PeriodData section visible. This section is on by default.
  • Comments section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
  • Options section – Temporal options and settings:
    • Time units drop-down – Time unit label used in output files. Contains a drop-down menu with the following options for the type of time units:
      • "Unknown"
      • "Seconds"
      • "Minutes"
      • "Hours"
      • "Days" – The default selection.
      • "Years"
    • Start date/time – Starting date and time. Turn on to enable setting a start date/time. Included in the list file using the selected time/date. Click the Date/Time... button to bring up the Date/Time dialog. The time can also be manually entered using "YYYY-MM-DDTHH:MM:SS" format. The "T" in the middle divides the date from the time.
  • PeriodData section – Contains a spreadsheet listing periods. An Row-add.svg Add Row button is found at the top rigth of the spreadsheet. Right-clicking on the row number in the spreadsheet gives a menu that allows inserting, deleting, copying, or pasting a row. The columns in the spreadsheet include:
    • PERLEN – The length of a stress period. The default value is "1.0".
    • NSTP – The number of time steps in a stress period. The default value is "1".
    • TSMULT – The multiplier for the length of successive time steps. The default value is "1.0".
    • ENDDATE – The end date for that period. This field is not directly user-editable, but will automatically change if the PERLEN value is changed.
    • STEADY-STATE GWF_Model – Turn on if the period is steady state and using the GWF Model.


CHD

MODFLOW 6
Models & Tools
GWF Model
GWT Model
Cell Properties Dialog
Zone File
Packages
Flow: GNC, HFB, NPF
GWF: BUY, CHD, CSUB,
DRN, EVT, GHB,
LAK, MAW, MVR,
OBS, RCH,RIV,
SFR, STO, UZF,
WEL
GWT: ADV, CNC, DSP
FMI, IC, IST, LKT,
MDT, MST, MVT,
MWT, OBS, SFT,
SRC,SSM, UZT
Other DIS, DISU, DISV,
IMS, OC, TDIS,
PEST
v • e

The Constant-Head (CHD) Package dialog

The Constant-Head (CHD) Package dialog is accessed by double-clicking on the CHD package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

  • Sections list – A list of sections that can be turned on or off:
    • Comments – Turn on to make the Comments section visible.
    • Options – Turn on to make the Options section visible.
    • Periods – Turn on to make the Periods section visible. This section is on by default.
  • Comments section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
  • Options section – Contains the following:
    • AUXILIARY – Click the Auxiliary Variables... button to bring up the Auxiliary Variables dialog.
    • AUXMULTNAME – Auxiliary variable used as multiplier of CHD head value. Enter the name of auxiliary variable to be used as multiplier of CHD head value.
    • BOUNDNAMES – Allow boundary names. Turn on to allow boundary names to be included in the list of constant-head cells.
    • PRINT_INPUT – Print input to listing file. Turn on to write the list of constant-head information to the listing file immediately after it is read.
    • PRINT_FLOWS – Print flows to listing file. Turn on to write the list of constant-head flow rates to the listing file for every stress period time step in which "BUDGET PRINT" is specified in Output Control.
    • SAVE_FLOWS – Save flows to budget file. Turn on to write constant-head flow terms to the file specified with "BUDGET FILEOUT" in Output Control.
    • TS6 FILEIN – Define time series files. Click the Files... button to bring up the Time Series Files dialog.
    • OBS6 FILEIN – Dfine observation files. Click teh Files... button to bring up the Observation Files dialog.
  • Periods section – Contains the following:
    • Period value – Use the Increment Up and Down Increment up and down arrows.png buttons to select the desired period.
    • Define Period Add Note Icon.svg – If no period is defined, click to make the spreadsheet editable.
    • Delete Period GMS Delete Icon.svg – Click to delete the existing period.
    • Add Rows Row-add.svg – Click to bring up the Add Stresses dialog.
    • Delete Rows Row-delete.svg – Click to bring up a dialog with three options:
      • Delete from All Periods – Click to delete matching stresses from all periods.
      • Delete from Just This Period – Click to delete matching stresses from just this period.
    • Plot All Periods Mf6time-series.svg – Click to bring up the XY Series Editor dialog. Requires that a cell be selected in the table.
    • Open Time Series Open Macro.svg – Click to bring up the
    • Filter on Selected Cells Mf6filter.svg – Click to turn on filtering on the selected cells.
      • Table – Contains the following:
        • LAY – Used to specify which layer is being applied.
        • CELL2D – Enter the cell ID that is being applied.
        • HEAD – Represents the head at the boundary.


DRN

MODFLOW 6
Models & Tools
GWF Model
GWT Model
Cell Properties Dialog
Zone File
Packages
Flow: GNC, HFB, NPF
GWF: BUY, CHD, CSUB,
DRN, EVT, GHB,
LAK, MAW, MVR,
OBS, RCH,RIV,
SFR, STO, UZF,
WEL
GWT: ADV, CNC, DSP
FMI, IC, IST, LKT,
MDT, MST, MVT,
MWT, OBS, SFT,
SRC,SSM, UZT
Other DIS, DISU, DISV,
IMS, OC, TDIS,
PEST
v • e

The Drain (DRN) Package dialog

The Drain (DRN) Package dialog is accessed by double-clicking on the DRN package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

  • Sections list – A list of sections that can be turned on or off:
    • Comments – Turn on to make the Comments section visible.
    • Options – Turn on to make the Options section visible.
    • Periods – Turn on to make the Periods section visible. This section is on by default.
  • Comments section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
  • Options section
    • AUXILIARY – Click the Auxiliary Variables... button to bring up the Auxiliary Variables dialog.
    • AUXMULTNAME – Auxiliary variable used as multiplier of CHD head value. Enter the name of auxiliary variable to be used as multiplier of CHD head value.
    • AUXDEPTHNAME – Auxiliary variable defining depth at which drainage discharge will be scaled.
    • BOUNDNAMES – Allow boundary names. Turn on to allow boundary names to be included in the list of constant-head cells.
    • PRINT_INPUT – Print input to listing file. Turn on to write the list of constant-head information to the listing file immediately after it is read.
    • PRINT_FLOWS – Print flows to listing file. Turn on to write the list of constant-head flow rates to the listing file for every stress period time step in which "BUDGET PRINT" is specified in Output Control.
    • TS6 FILEIN – Define time series files. Click the Files... button to bring up the Time Series Files dialog.
    • OBS6 FILEIN – Dfine observation files. Click teh Files... button to bring up the Observation Files dialog.
    • MOVER – Can be used with the Water Mover (MVR) package. Turn on to allows this instance of the Drain Package to be used with the Water Mover (MVR) Package.
  • Periods section – Contains the following:
    • Period drop-down – Use the Increment Up and Down Increment up and down arrows.png buttons to select the desired period.
    • Define Period Add Note Icon.svg – If no period is defined, click to make the spreadsheet editable.
    • Delete Period GMS Delete Icon.svg – Click to delete the existing period.
    • Add Rows Row-add.svg – Click to bring up the Add Stresses dialog.
    • Delete Rows Row-delete.svg – Click to bring up a dialog with three options:
      • Delete from All Periods – Click to delete matching stresses from all periods.
      • Delete from Just This Period – Click to delete matching stresses from just this period.
    • Plot All Periods Mf6time-series.svg – Click to bring up the XY Series Editor dialog. Requires that a cell be selected in the table.
    • Open Time Series Open Macro.svg – Click to bring up the
    • Filter on Selected Cells Mf6filter.svg – Click to turn on filtering on the selected cells.
      • Table – Contains the following:
        • LAY – Used to specify which layer is being applied.
        • CELL2D – Enter the cell ID that is being applied.
        • ELEV – Represents the elevation of the drain.
        • COND – Represents the hydraulic conductance between the aquifer and the drain.

EVT

GHB

GNC

HFB

LAK

MAW

MVR

OBS

OC

NPF

RCH

RIV

SFR

STO

UZF

WEL

Simulations Options

New Conceptual Model

New Simulation dialog

New MODFLOW 6 Simulation Dialog

This dialog appears when a new MODFLOW 6 simulation is first created. The dialog has the following options:

  • Simulation name – A name for the simulation can be entered in this field.
  • Select UGrid – This section will contain a list of available UGrids to use in the MODFLOW 6 simulation. A UGrid must be selected before the simulation can be created.
  • Optional packages – This section contains a list of available optional packages that be included when the simulation is created. Packages are listed for both flow and transport model types. The model type must be selected to select the packages associates with the model type. The packages are organized by the model type.
A message at the bottom of this section will state which packages are already included in the simulation being created.
Example of the New MODFLOW 6 Simulation dialog

IMS Package

The Iterative Model Solution (IMS) dialog

The Iterative Model Solution (IMS) dialog is accessed by double-clicking on the IMS package under a MODFLOW 6 simulation in the Project Explorer. It contains the following sections and options:

  • Sections list – A list of sections that can be turned on or off:
    • Comments – Turn on to make the Comments section visible.
    • Options – Turn on to make the Options section visible.
    • Nonlinear – Turn on to make the Nonlinear section visible. This section is on by default.
    • Linear – Turn on to make the Linear section visible. This section is on by default.
  • Comments section – Enter general alphanumeric comments. Comments entered here get written at the top of the file, preceded by a '#' symbol.
  • Options section
    • PRINT_OPTION – A flag that controls printing of convergence information from the solver. Turn on to make the following print options available from the drop-down:
      • "None" – Print nothing. This is the default when PRINT_OPTION is not turned on.
      • "Summary" – Print only the total number of iterations and nonlinear residual reduction summaries
      • "All" – Print linear matrix solver convergence information to the solution listing file and model specific linear matrix solver convergence information to each model listing file in addition to "Summary" information.
    • COMPLEXITY – Optional. Defines default non-linear and linear solver parameters. Turn on to make the following options available from the drop-down:
      • "Simple" – Default solver input values will be defined that work well for nearly linear models.
      • "Moderate" – Default solver input values will be defined that work well for moderately nonlinear models.
      • "Complex" – Default solver input values will be defined that work well for highly nonlinear models.
      • Set NONLINEAR and LINEAR Parameters to Complexity Defaults – This will set all nonlinear and linear parameters to their default values corresponding to the current complexity setting. A confirmation dialog will appear.
    • CSV_OUTER_OUTPUT FILEOUT – Turn on to specify that the record corresponds to the comma separated values solver convergence output. Enter the desired filename for the output ASCII CSV file in the empty field to the right of the option.
    • CSV_INNER_OUTPUT FILEOUT – Turn on to specify that the record corresponds to the comma separated values solver convergence output. Enter the desired filename for the output ASCII CSV file in the empty field to the right of the option.
    • NO_PTC – Turn on to disable pseudo-transient continuation (PTC). Only applies to steady-state stress periods for models using the Newton-Raphson formulation.
      • "ALL"
      • "FIRST"
  • Nonlinear section – A table with three columns: "Use" to turn on or off options, "Option" (giving the name of the option), and "Value", where a value can be entered for the option. The options include the following:
    • OUTER_DVCLOSE – Real value defining the head change criterion for convergence of the outer (nonlinear) iterations, in units of length. Default value is "0.001".
    • OUTER_MAXIMUM – Integer value defining the maximum number of outer (nonlinear) iterations. Default value is "25".
    • UNDER_RELAXATION – Optional drop-down value. Defines the nonlinear under-relaxation schemes used.
      • "None" – Under-relaxation is not used.
      • "Simple" – Simple under-relaxation scheme with a fixed relaxation factor is used.
      • "Cooley" – Cooley under-relaxation scheme is used.
      • "DBD" – Delta-bar-delta under-relaxation is used.
    • UNDER_RELAXATION_THETA – Real value defining the reduction factor for the learning rate (under-relaxation term) of the delta-bar-delta algorithm. Default value is "0.0".
    • UNDER_RELAXATION_KAPPA – Real value defining the increment for the learning rate (under-relaxationterm) of the delta-bar-delta algorithm. Default value is "0.0".
    • UNDER_RELAXATION_GAMMA – Real value defining the history or memory term factor of the delta-bar-delta algorithm. Default value is "0.0".
    • UNDER_RELAXATION_MOMENTUM – Real value defining the fraction of past history changes that is added as a momentum term to the step change for a nonlinear iteration. Default value is "0.0".
    • BACKTRACKING_NUMBER – Integer value defining the maximum number of backtracking iterations allowed for residual reduction computations. Default value is "0".
    • BACKTRACKING_TOLERANCE – Only available if BACKTRACKING_NUMBER" has a value of "1" or higher. Real value defining the tolerance for residual change that is allowed for residual reduction computations
    • BACKTRACKING_REDUCTION_FACTOR – Only available if BACKTRACKING_NUMBER" has a value of "1" or higher. Real value defining the reduction in step size used for residual reduction computations
    • BACKTRACKING_RESIDUAL_LIMIT – Only available if BACKTRACKING_NUMBER" has a value of "1" or higher. Real value defining the limit to which the residual is reduced with backtracking.
    • LINEAR_SOLVER – Enter the linear solver being used.
  • Linear section – A table with three columns: "Use" to turn on or off options, "Option" (giving the name of the option) and "Value", where a value can be entered for the option. The options include the following:
    • INNER_MAXIMUM – Integer value defining the maximum number of inner (linear) iterations. Default value of "50".
    • INNER_DVCLOSE (length) – Real value defining the head change criterion for convergence of the inner (linear) iterations, in units of length. Default value of "0.001".
    • INNER_RCLOSE (length3/time) – Real value that defines the flow residual tolerance for convergence of the IMS linear solver and specific flow residual criteria used. Default value of "0.1".
    • RCLOSE_OPTION – Optional. Defines the specific flow residual criterion used. Default selection of "None". Has the following options:
      • "None" – If selected, an absolute residual (infinity-norm) criterion is used.
      • "Strict" – Specifies that INNERRCLOSE represents an infinity-Norm (absolute convergence criteria) and that the head and flow convergence criteria must be met on the first inner iteration.
      • "L2NORM_RCLOSE" – Specifies that INNERRCLOSE represents a L-2 Norm closure criteria instead of an infinity-Norm (absolute con-vergence criteria).
      • "RELATIVE_RCLOSE" – Spcifies that INNERRCLOSE represents a relative L-2 Norm reduction closure criteria instead of an infinity-Norm (absolute convergence criteria).
    • LINEAR_ACCELERATION – Defines the linear acceleration method used by the default IMS linear solvers. Default selection of "CG". Has the following options:
      • "CG" – Preconditioned conjugate gradient method.
      • "BICGSTAB" – Preconditionedbi-conjugate gradient stabilized method.
    • RELAXATION_FACTOR – Optional. Real value that defines the relaxation factor used by the incomplete LU factorization preconditioners (MILU(0) and MILUT). Default value of "0.0".
    • PRECONDITIONER_LEVELS – Optional. Integer value defining the level of fill for ILU decomposition used in the ILUT and MILUT preconditioners. Default value of "0".
    • PRECONDITIONER_DROP_TOLERANCE – Optional. Real value that defines the drop tolerance used to drop preconditioner terms based on the magnitude of matrix entries in the ILUT and MILUT preconditioners. Default value of "0.0".
    • NUMBER_ORTHOGONALIZATIONS – Optional. Integer value defining the interval used to explicitly recalculate the residual of the flow equation using the solver coefficient matrix, the latest head estimates, and the right hand side. Default value of "0".
    • SCALING_METHOD – Optional. Defines the matrix scaling approach used. Default selection of "None". Has the following options:
      • "None" – No matrix scaling applied.
      • "Diagonal" – Symmetric matrix scaling using the POLCG preconditioner scaling method.
      • "L2NORM" – Symmetric matrix scaling using the L2 norm.
    • REORDERING_METHOD – Optional. Defines the matrix reordering approach used. Default selection of "None". Has the following options:
      • "None" – Original ordering.
      • "RCM" – Reverse Cuthill McKee ordering.
      • "MD" – Minimum degree ordering.

MODFLOW 6 Right-Click Menu

In the Project Explorer, right-clicking on MODFLOW 6 simulation brings up a menu with several commands. Some of these commands are common to other Project Explorer right-click menus. Others are unique to the simulation right-click menus. Some of these unique commands are:

  • "Mf6sim data.svg Simulation Data"
    • Simulation Run Queue – Opens the Simulation Run Queue dialog which shows all current simulation runs.
  • "MF6 Simulation Folder.svg MODFLOW 6 Simulations"
    • New Simulation – Creates a new MODFLOW 6 simulation in the Project Explorer. This simulation will not contain any of the packages in any existing simulations and therefor the packages must be added. Also, creating a new simulation using this method requires linking a UGrid to the simulation.
    • Simulation Run Queue – Opens the Simulation Run Queue dialog which shows all current simulation runs.
    • Save All and Run – Saves all MODFLOW 6 simulations in the project and exports all files needed for the model run. It then will launch the Simulation Run Queu dialog and begin the model runs for all simulations in the project.
  • MODFLOW Folder.svg Model
    • Simulation Run Queue – Opens the Simulation Run Queue dialog which shows all current simulation runs.
    • New Package – Opens a sub-menu listing all available packages that can be added to the simulation. Selecting a package will add it to the simulation. Some packages cannot be added until certain packages have already been added to the simulation and therefore will not be available until the prerequisite package has been added.
    • Check Simulation – Checks the simulation for model errors and brings up the Model Check dialog if any errors are found.
    • Save Simulation – Saves the simulation and exports all files needed for the model run.
    • Run Simulation – Starts the simulation model run and opens the Simulation Run Queue dialog.
    • Save Project, Simulation and Run – Saves the simulation and exports all files needed for the model run. It then will launch the Simulation Run Queu dialog and begin the model runs for the simulation.
    • Read Solution – Loads the solution file for the associated simulation. Requires that the simulation has had a successful run.

Unsupported Features

In GMS, some features of MODFLOW 6 are not yet supported or only have minimal support. These include:

  • MODFLOW 6 features
    • Only support for one SOLUTIONGROUP in the mfsim.nam file
    • ‘NONE’ for cellid in SFR PACKAGEDATA block is not supported
    • IPRN variable for arrays
    • Advanced package output files
  • GMS interface functionality
    • Conceptual model approach for some packages
    • Observations coverage
    • Cell properties for array-based RCH and EVT packages

The MODFLOW 6 export option does not function with projects that are incompatible with MODFLOW 6. Projects with unsupported features or parameters will not be successfully exported.

Not all MODFLOW packages are supported in MODFLOW 6. The following table shows the correlation between MODFLOW 6 packages and packages from previous versions of MODFLOW.

MODFLOW 6 supported packages Equivalent Mf2k5/USG package
CHD, DRN, GHB, RIV, WEL CHD, DRN, GHB, RIV, WEL
DIS, DISV, DISU, TDIS DIS, DISU
EVT, RCH EVT, ETS, RCH
GNC GNC
IC BAS
LAK LAK
MAW MNW2
NPF, STO BCF, HUF, LPF, UPW
SFR SFR
UZF UZF
MVR, GWF, OBS Not supported
Not Supported DRT, GAGE, MNW1, MNWI, STR, SUB, SWI, OBS, HOB, CHOB, RVOB, STOB, DROB
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