detran_tutorial tutorial for Detran

To open the GUI, just type call detran without input arguments.

detran

The use of the graphical user interface is illustrated in more detail in a video tutorial

To use Detran in command line mode, you have to specify some input arguments. If we have for example a single trim-file, and we want to calculate the transport through a certain transect with coordinates (2260,5333) to (5798,1797), then we use the following command to calculate the transport through this transect:

trimfile='testmodel\trim-example.dat';
transect = [200 150 450 150];
tr = detran('single',trimfile,'transects',transect,'transType',...
    {'total','mean'},'fraction',0,'timeStep',0);
disp(['The transport rate through the transect is ' num2str(3600*tr,'%5.0f') ' m3/hr'])

Because a couple of the specified input arguments are default values, they can be omitted:

tr = detran('single',trimfile,'transects',transect);
disp(['The transport rate through the transect is ' num2str(3600*tr,'%5.0f') ' m3/hr']);

The example trim file contains two sediment fractions. If you want to extract the transport rate for each fraction seperately, you enter:

tr1 = detran('single',trimfile,'transects',transect,'fraction',1);
tr2 = detran('single',trimfile,'transects',transect,'fraction',2);
disp(['The transport rate of fraction 1 through the transect is ' num2str(3600*tr1,'%5.0f') ' m3/hr']);
disp(['The transport rate of fraction 2 through the transect is ' num2str(3600*tr2,'%5.0f') ' m3/hr']);

Logically, tr1 + tr2 = tr!

disp(['The total transport rate through the transect is: ' num2str(3600*(tr1+tr2),'%5.0f') ' m3/hr']);

It is also possible to define more than one trasect:

transect = [200 150 450 150;...
            450 150 700 150;...
            450 310 450 150;...
            200 150 200 10;...
            700 150 700 10];
tr = detran('single',trimfile,'transects',transect);
disp(num2str(3600*tr,'%5.0f'));

By specifying 3 output arguments, detran also gives the gross transport rates (positive and negative):

[tr,tp,tn] = detran('single',trimfile,'transects',transect);
disp(num2str(3600*[tr tp tn],'%5.0f'));

Since the transport is uniformly directed along the transect, one of the gross transport components is 0.

Detran can also be used to read the transport rate through the cross sections as specified in the model input. This information is stored in the history output file of Delft3D (trih-file). As a consequence you do not need to specify transect information as input argument when using trih-files:

trihfile='testmodel\trih-example.dat';
tr = detran('single',trihfile);
disp(num2str(3600*tr,'%5.0f'));

Because nine cross sections have been defined in the Delft3D input, three transport rates are returned by Detran. Note that the cross sections (and thus the resulting transpor rates) are identical to those used for the example with trim-input.

Also for trih-files it is possible to calculate the transport rate per fraction:

tr = detran('single',trihfile,'fraction',1);
disp(num2str(3600*tr,'%5.0f'));

The resulting transport rates and their corresponding transects can also easily be plotted using 'detran_plotTransportThroughTransect' from the Detran toolbox:

trimfile='testmodel\trim-example.dat';
transect = [200 150 450 150;...
            450 150 700 150;...
            450 310 450 150;...
            200 150 200 10;...
            700 150 700 10];
tr = detran('single',trimfile,'transects',transect);
ldb=[0     0 195 195 205 205 695 695 705 705 900 900;...
     400 310 310 150 150 310 310 150 150 310 310 400]';
figure;
patch(ldb(:,1),ldb(:,2),[1 1 0.5]);
hold on;
for t=1:size(transect,1)
    detran_plotTransportThroughTransect(transect(t,1:2),transect(t,3:4),3600*tr(t),10);
end
title('transport rate though transects in m^3/hr!');
xlabel('x (m)');
ylabel('y (m)');

You can also plot the gross transport rates:

[tr tp tn] = detran('single',trimfile,'transects',transect);
figure;
patch(ldb(:,1),ldb(:,2),[1 1 0.5]);
hold on;
for t=1:size(transect,1)
    detran_plotTransportThroughTransect(transect(t,1:2),transect(t,3:4),3600.*[tr(t) tp(t) tn(t)],10);
end
title('transport rate though transects in m^3/hr!');
xlabel('x (m)');
ylabel('y (m)');