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#1
haris179

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Hi guys!

can i get height of some place using DEM? i have converted the DEM into contours but dint get the data i want. is there any way of getting height using DEM?

#2
frax

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haris, a DEM is elevations, most likely you have a grid/raster data originally - you should be able to get the height out of that, by just clicking on the point in the raster file and getting the value where you click. (of course you can do more fancy things - like doing an overlay and getting the height of points that you have)

The contours you have created should be isolines at a specified interval (5m? 10m?) and the lines that you get should have the height as an attribute.

What software are you using, and what DEM data?
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#3
haris179

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haris, a DEM is elevations, most likely you have a grid/raster data originally - you should be able to get the height out of that, by just clicking on the point in the raster file and getting the value where you click. (of course you can do more fancy things - like doing an overlay and getting the height of points that you have)

The contours you have created should be isolines at a specified interval (5m? 10m?) and the lines that you get should have the height as an attribute.

What software are you using, and what DEM data?


i am using arcgis 9.1, didnt try in ERDAS yet. i am using 5m. it doesnt have height i dono y. or there is any other way of getting it ?

#4
aug_aug

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I think we should start over here, can you provide a link to the dem? Or at least describe where you obtained it from and what units it is in.

The prior post is correct, if you want elevations for specific points simply load the DEM into ArcMap and use the information tool, it looks like a blue circle with the letter "i" inside of it and click the location that you want to know the elevation of.

If you already have contours, you could follow this guide: http://www.esri.com/...oolglaciers.pdf and finish your contour map with labels, then you could actually read the elevations off of your map.

Hope this helps, write back with more info if you get stuck.

#5
haris179

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that link was very useful thanks alot. but i dont know whats wrong with my dem. it is referenced but when i get the info it gives my pixel value thats it. going through info button we can get the required data but in this case i cant find a way of getting through. i think the data given to me is incomplete.

#6
frax

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the pixel value should be the height. What is the info you get when you inspect the file - what does the values look like? (you can get figures off depending on the format and how you import it, especially for floating point and signed values)

If your "DEM" doesn't have height/elevation/y-values/pixels then everything is off with it - it isn't an elevation model basically...
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#7
haris179

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the pixel value should be the height. What is the info you get when you inspect the file - what does the values look like? (you can get figures off depending on the format and how you import it, especially for floating point and signed values)

If your "DEM" doesn't have height/elevation/y-values/pixels then everything is off with it - it isn't an elevation model basically...

it only gives the the pixel value, i think i should compare the pixel value with the known height value of some place.

#8
David Medeiros

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the pixel value should be the height. What is the info you get when you inspect the file - what does the values look like? (you can get figures off depending on the format and how you import it, especially for floating point and signed values)

If your "DEM" doesn't have height/elevation/y-values/pixels then everything is off with it - it isn't an elevation model basically...

it only gives the the pixel value, i think i should compare the pixel value with the known height value of some place.


As mentioned above the pixel value of a DEM is the height, though it will only show up in the information display as a number with no annotation such as ft or m. If the numbers seem unrecognizable in terms of what you are expecting to see for elevations at your locations, remember that your DEM may be in either feet or meters and might require a conversion to get the units you want.

GIS Reference and Instruction Specialist, Stanford Geospatial Center.

 

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#9
haris179

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the pixel value should be the height. What is the info you get when you inspect the file - what does the values look like? (you can get figures off depending on the format and how you import it, especially for floating point and signed values)

If your "DEM" doesn't have height/elevation/y-values/pixels then everything is off with it - it isn't an elevation model basically...

it only gives the the pixel value, i think i should compare the pixel value with the known height value of some place.


As mentioned above the pixel value of a DEM is the height, though it will only show up in the information display as a number with no annotation such as ft or m. If the numbers seem unrecognizable in terms of what you are expecting to see for elevations at your locations, remember that your DEM may be in either feet or meters and might require a conversion to get the units you want.


thanks alot bro!




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