Distance Meassurement

[MarioOssovsky]

Dear Ladies and Gentlemen,

for my masters-thesis I'm looking for a Tool in ArcMap, that allows me to measure the distance to the nearest object, just like with the Near Tool (Analysis Toolbox>Proximity>Near). Only I need the distanc to be measured only to Features, which are e.g. south of my Input Features or, even better would be to measure the distance to a feature which is south of a fictional east-west-line through the Input-Feature (which is a point featur class in my case), since only those features influence my points.

I hope you can understand my problem and maybe somebody could offer a solution.

Thanks in advance,

Mario

[DavidLednik]

Hi,

You could pass a subset of features that are south of the feature you're trying to get the nearest feature.

You will probably have to code something that iterates through input features and passes subset to the near tool to get the desired result.

Regards,

David

[MarioOssovsky]

Hi David,

thank's a lot for the quick answer. I'm not sure though if it completely fixes my problem. I think I need to specify my problem a little more too.

I'd like to measure the influence of subsurface buildings (like subway tunnels) on groundwater temperatures. So my data consists of about 1000 GW Measurings Stations with temperature measurments (my input point-feature-class) which are distributed amongst the different subway lines (my near feature as a line-feature class). Since the groundwater flow is from south to north, only distances to subway tunnels which are upstream of the groundwater flow (in my case south) should be accounted, even though there might be a closer one downstream the measurment station. since the temperature cannot propagate upstream.

I need to do this for about 10 different feature classes that might influence the temperature so it would be good to find a way of fixing it without having to handpick every single station or line of the subway etc.

thanks

[DavidLednik]

Hi Mario,

You don't need to do it completely manually.

But you will need to write a tool either as an ArcMap extension or maybe a python script.

So it can be done just not with the out of the box tools. You will need to combine them to get the valid results for the scenario you described.

I still think writing a ArcMap extension is the best way to do it. Just calculate results for each of the measuring station by filtering the data.

Just had an idea. You could divide your data into horizontal bands. And assign attribute values to measuring stations and buildings which band it belongs to. By applying filter by attributes you could use standard tool to get the results back. But again you would need to prep the data for that step. Should be easier if you're not to keen to write ArcObjects code.

David

[MarioOssovsky]

Hi David,

do You think it might be possible do include a if-then question in the Near Tool, so if the Near_Angle is within a certain range e.g. 0 to -90 (=east to west via south) the Near_Distance value should be kept, otherwise ArcGIS shoul compute the next possible Objekt until the angle is within that range?

Mario