# Grid and Computational Time¶

**SPECIFICATION OF DIMENSION**

`Mglob`

: global dimension in x direction.`Nglob`

: global dimension in y direction.

**SPECIFICATION OF GRID SIZE**

`DX`

: grid size(m) in x direction.`DY`

: grid size(n) in y direction.

**SPECIFICATION OF WATER DEPTH**

`DEPTH_TYPE`

: depth input type.

The program includes several simple bathymetry configurations such as:

`DEPTH_TYPE = DATA`

: from a depth file.

`DEPTH_TYPE = FLAT`

: flat bottom, need`DEPTH_FLAT`

`DEPTH_TYPE = SLOPE`

: plane beach along x direction. It needs three parameters: slope,`SLP`

, slope starting point,`Xslp`

and flat part of depth,`DEPTH_FLAT`

.

`DEPTH_FILE`

: name of bathymetry file, if`DEPTH_TYPE = DATA`

. The file dimensions should be the same as`Mglob x Nglob`

with the first point as the south-west corner. The read format in the code is shown below:DO J=1,Nglob READ(1,*)(Depth(I,J),I=1,Mglob) ENDDO

`DEPTH_FLAT`

: water depth of flat bottom if`DEPTH_TYPE = FLAT`

or`DEPTH_TYPE = SLOPE`

(flat part of a plane beach).`SLP`

: slope if`DEPTH_TYPE = SLOPE`

.`Xslp`

: starting x (m) of a slope, if`DEPTH_TYPE = SLOPE`

.`WaterLevel`

: Specify a water level which will be added to the input bathymetry and wavemaker depth such as`DEP_WK`

(internal wave generator) and`DepthWaveMaker`

(left boundary generator).

Note

IF you add surge or tide level using

`WaterLevel`

, please keep`DEP_WK`

the same as the original depth in the depth file because the water level will be automatically added to the model bathymetry.

**SPECIFICATION OF TIME**

`TOTAL_TIME`

: simulation time in seconds.`PLOT_INTV`

: output interval in seconds (Note, output time is not exact because adaptive`dt`

is used.)`SCREEN_INTV`

: time interval (s) of screen print.`PLOT_INTV_STATION`

: time interval (s) of gauge output.`PLOT_START_TIME`

: start time for output of field results (s). Default: 0.0`DT_fixed`

: time step (s) if use fixed DT. But`DT_fixed`

will be checked by the CFL condition. IF`DT_fixed`

does not satisfy CLF, DT/2, DT/4 … will be checked until it satisfies CFL. Default is using variable DT based on CFL.