# Simulation

## Time

Configure the number or years to run the simulation and time step. If you have observed weather data, make sure your simulation time falls within these dates.

| SWAT+ Input File | Database Table |
| ---------------- | -------------- |
| time.sim         | time\_sim      |

### time\_sim

| Field | Type | Description |
| ----- | ---- | ----------- |

| id | int | Auto-assigned identifier |
| -- | --- | ------------------------ |

| day\_start | int | <p>Beginning Julian day of simulation</p><p>If zero, the model starts the simulation on January 1</p> |
| ---------- | --- | ----------------------------------------------------------------------------------------------------- |

| day\_end | int | <p>Ending Julian day of simulation</p><p>If zero, the model ends the simulation on December 31</p> |
| -------- | --- | -------------------------------------------------------------------------------------------------- |

| step | int | Time steps in a day for rainfall, runoff and routing |
| ---- | --- | ---------------------------------------------------- |

Configure the output files to print.

| SWAT+ Input File | Database Tables    |
| ---------------- | ------------------ |
| print.prt        | print\_prt         |
|                  | print\_prt\_object |

### print\_prt

| Field      | Type | Description                                                                               |
| ---------- | ---- | ----------------------------------------------------------------------------------------- |
| id         | int  | Auto-assigned identifier                                                                  |
| nyskip     | int  | Number of years to *not* print output                                                     |
| day\_start | int  | Beginning Julian day of simulation to start printing output files for daily printing only |
| yrc\_start | int  | Beginning year of simulation to start printing output files                               |
| day\_end   | int  | Ending Julian day of simulation to stop printing output files for daily printing only     |
| yrc\_end   | int  | Ending year of simulation to stop printing output files                                   |
| interval   | int  | Daily print within the period (e.g., interval=2 will print every other day)               |
| csvout     | bool | Print .csv files in addition to text files                                                |
| dbout      | bool | Print database (not currently active)                                                     |
| cdfout     | bool | Print netcdf (not currently active)                                                       |
| soilout    | bool | Print soil nutrients carbon output file                                                   |
| mgtout     | bool | Print management output file                                                              |
| hydcon     | bool | Print hydrograph connect output file                                                      |
| fdcout     | bool | Print flow duration curve output file                                                     |

### print\_prt\_object

Each row in print\_prt\_object represents an output file that can be print daily, monthly, yearly, and average annual output for each.

| Field          | Type | Description                 |
| -------------- | ---- | --------------------------- |
| id             | int  | Auto-assigned identifier    |
| print\_prt\_id | int  | ID of print\_prt row        |
| name           | text | Name of print object        |
| daily          | bool | Print daily output          |
| monthly        | bool | Print monthly output        |
| yearly         | bool | Print yearly output         |
| avann          | bool | Print average annual output |

{% hint style="info" %}
Daily printing of all files could cause very large output (exceeding hard drive space)
{% endhint %}

#### Print Object Descriptions

| Object Name     | Description                                    |
| --------------- | ---------------------------------------------- |
| basin\_wb       | Water balance basin output variables           |
| basin\_nb       | Nutrient balance basin output variables        |
| basin\_ls       | Losses basin output variables                  |
| basin\_pw       | Plant weather basin output variables           |
| basin\_aqu      | Aquifer basin output variables                 |
| basin\_res      | Reservoir basin output file variables          |
| basin\_cha      | Channel basin output file variables            |
| basin\_sd\_cha  | CHAN DEG basin output file variables           |
| basin\_psc      | Point source basin output file variables       |
| region\_wb      | Water balance region output variables          |
| region\_nb      | Nutrient balance region output variables       |
| region\_ls      | Losses region output variables                 |
| region\_pw      | Plant weather region output variables          |
| region\_aqu     | Aquifer region output variables                |
| region\_res     | Reservoir region output variables              |
| region\_cha     | Channel region output variables                |
| region\_sd\_cha | SWAT DEG Channel region output variables       |
| region\_psc     | Point source region output variables           |
| lsunit\_wb      | Water balance routing unit output variables    |
| lsunit\_nb      | Nutrient balance routing unit output variables |
| lsunit\_ls      | Losses routing unit output variables           |
| lsunit\_pw      | Plant weather routing unit output variables    |
| hru\_wb         | Water balance hru output variables             |
| hru\_nb         | Nutrient balance hru output variables          |
| hru\_ls         | Losses hru output variables                    |
| hru\_pw         | Plant weather hru output variables             |
| hru-lte\_wb     | Water balance HRU-LTE output variables         |
| hru-lte\_nb     | Nutrient balance HRU-LTE output variables      |
| hru-lte\_ls     | Losses HRU-LTE output variables                |
| hru-lte\_pw     | Plant weather HRU-LTE output variables         |
| channel         | Channel output variables                       |
| channel\_sd     | SWAT DEG (lte) channel output variables        |
| aquifer         | Aquifer output variables                       |
| reservoir       | Reservoir output variables                     |
| recall          | Recall output variables                        |
| hyd             | Hydin output and hydout\_output variables      |
| ru              | Routing unit output variables                  |
| pest            | Pesticide constituents outputs                 |


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