network analysis on selection of network?

[PeterGroote]

Hi there,

I have built a historical dataset of a transport network, with the year of construction of each road/railroad section as an attribute. I would like to perform several network anlyses (OD-matrix) on it, for specific years. So a first analysis on the OD-distances in 1850, and then one for 1875. How do I select only the subnet that existed in a specific year.
My first thought was to simply select by attribute in the feature class and run the network analysis, but that does not work. Then I thought of using restrictions in the network analysis, but I do not understand how to use the attributes from the original feature class as a boolean operator in the network dataset.
Am I overlooking something simple?

TIA, Peter

[MichaelRice]

Using restriction attributes sounds like the correct approach for you. To understand how to create restriction attributes for your field values, I would suggest to work through the Network Analyst tutorial (for which you should have sample data as well). This should give you a better understanding of how to set up your network dataset for such analysis.

[Igordel_Rio]

In Arcgis 10 is more simple, in 9.xx, you can use varely approaches,

example 1, fields of table, 1950 and 1975, build a network with 1950 colum and another with 1975 collum.

Add ND 1950 or 1975 ND

example 2 , use the case of bridge weights, i think you cant define a restrition to use 1950 instead 1975 and vs

[MichaelRice]

Igor,

You can create multiple restriction attributes (to represent different years) in a single network dataset at both 9.x and 10. There is no need to create multiple network datasets.