Replies to This Discussion

Permalink Reply by Hayden on August 9, 2010 at 5:32am

can elaborate more detail?

• ▶ Reply

Permalink Reply by Upaka on August 9, 2010 at 5:41am

thanks a lot for your reply.

I mean when we link the SWMM 5.0 with another software module, we have to call the results from the programming language, what we are using.

I am using c++ to link SWMM 5.0 with NSGA II (an optimization module) to do my research work.
In this case I have to get some results from the SWMM 5.0 to run the optimization module and the SWMM 5.0 interfacing guide has given some details, but bit confusing.

The results calling function should be able to identify the particular item in order to get the exact result of it.

The guide gives the following but I can't understand how to use the "item index" in a situation as described follows.

Think there are 5 weirs and 2 orifices in a network and one wanted to get the flow rates at orifices using the above mentioned "GetSwmmResult" function.



The guide gives;

The function GetSingleResult, which is included in the example code files that accompany this guide, demonstrates the code needed to retrieve the computed result for a particular variable for a given object at a specific point in time. The arguments to the function are:

itemType
the class of item being sought (input)

itemIndex
the index of the item being sought (input)

varIndex
the index of the variable being sought (input)

period
the index of the time period being sought, starting from 1(input)

value
the value of the result being sought (output).



The function returns a value of 1 if it was successful or a value of 0 if was not.

The choices for itemType can be:
· 0 for Subcatchments,

· 1 for Nodes

· 2 for Links

· 3 for System



The itemIndex argument identifies items of a given class that are reported on by consecutive numbers starting from 0, which are assigned in the same order as the item appeared in the SWMM 5 input file. As an example, suppose that a system contains 5 junction nodes with ID names J1, J2, J3, J4, and J5 that are listed in this same order in the project's input file, but output results are only requested for junctions J2 and J4. Then an itemIndex of 0 would retrieve results for J2 while an itemIndex of 1 would do the same for J4. Any other values for itemIndex would be invalid. For System items the itemIndex argument is ignored.

The choices for varIndex depend on the class of object being sought and are listed in the Output File - Reporting Variables topic of Appendix B.


Thanks alot

• ▶ Reply

Permalink Reply by Upaka on August 11, 2010 at 11:36am

I found the answer for my own question and would like paste it here if anyone needs it in future.


When results for all links are saved, then the ItemIndex is the order
(starting from 0) in which the Link is first defined in the input file.
For example, suppose your input file looked as follows:

[CONDUITS]
A
B
C

[WEIRS]
W1
W2

]PUMPS]
P1
P2

[ORIFICES]
O-A
O-B

Then the ItemIndex for weir W1 would be 3 while that for orifice O-B is
8.

If in the [REPORT] section you specify that results are only saved for
weir W1 and orifices O-A and O-B, then the item index of W1 is 0 and
that of O-B is 2 (even if you listed them as O-B, W1, and O-A in the
[REPORT] section, since the numbering is still relative to their
position where they are first defined in the input file).

• ▶ Reply

▶ Reply to Discussion