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#1
ghaney86

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I'm working on a project for a class in which I'm trying to figure out a GIS model for mountainous terrain. Basically, each point should have elev, slope, aspect, and I've got a bunch of temp data from data loggers that are the main point of the research. My professor suggested a fishnet, to capture all of the data into one "surface". The raster info is fine, I can create a fishnet with the interpolated elev, and each point in the fishnet has the elev. But the point data (data loggers) is an Excel file that I've converted into a point layer. I need to get this data (with years of temps) into the fishnet. I've never used a fishnet before a couple of weeks ago. Any help?

Or is there another, better tool that I should be using?

Any help would be great! Thanks,

Gerald

#2
Charlie Frye

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I would definitely recommend going the raster route. The tools to explore using are the interpolation tools. By using a raster the concept of cell size takes the place of the fishnet. I would suggest working with your professor to agree on the best tool for interpolating the points.

I'm working on a project for a class in which I'm trying to figure out a GIS model for mountainous terrain. Basically, each point should have elev, slope, aspect, and I've got a bunch of temp data from data loggers that are the main point of the research. My professor suggested a fishnet, to capture all of the data into one "surface". The raster info is fine, I can create a fishnet with the interpolated elev, and each point in the fishnet has the elev. But the point data (data loggers) is an Excel file that I've converted into a point layer. I need to get this data (with years of temps) into the fishnet. I've never used a fishnet before a couple of weeks ago. Any help?

Or is there another, better tool that I should be using?

Any help would be great! Thanks,

Gerald


Charlie Frye
Chief Cartographer
Software Products Department
ESRI, Redlands, California

#3
ghaney86

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Right. I can get the raster info into the fishnet easily, by extracting values to points, etc. But I can't get the point layer into the fishnet. Is this even possible?

#4
Irvin Feliciano

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Right. I can get the raster info into the fishnet easily, by extracting values to points, etc. But I can't get the point layer into the fishnet. Is this even possible?

I'm not sure what are you trying to do but i guess is: creating a a vector [Fish-net] that's resemblance a raster grid but with different values regarding some time term of the data you have in Excel. If that so, i suggest the following. Export the excel File into a .dbf file for the input on Arc GIS. Create points events with that .dbf file, and interpolate each time term information you have for those elevation data and save the raster with a proper name [so you don't mistake it]. Also remember to set the Spatial Analysis environment to the same cell size and extent for those rasters before you start generating them. Then you will convert all the new generated rasters into polygons and perform a Spatial Identity [so one of the polygon holds field and values of the other polygons] for all the fish-net you generated. When all info is combine you will have a single polygon fish-net with with different values stored on different fields. Then you perhaps will need whatever extra information you have on the dbf. data; so with the original events, you do again an Identity and delete the field you don't need. And you are done i guess.

Note: You need to create those rasters firsts and interpolate them because you already have an interpolated raster [as you mention before], so if you want to keep consistency in your study you also need apply the same interpolation method, cell size and extent you used before [elevation measurements behave the same (see interpolation methods on GIS)]. A simple Nearest-neighbor will do.

Good Luck!




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