| 17 Nov 2008 09:45 AM |
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Hi,there
I am a new user of ENVI, and have a question like this:
I got time-series MODIS data, and want to got a polt in which the X axias is the time (date) obtain from these data, and Y axias is the DN number (such as NDVI or EVI). How can I got it?
Do I need to realize it by using IDL programming, or The ENVI has the function?
pls reply in detail because I just learn ENVI from last week.
Many thanks for your help!
ps: I capy and paste this thread bucause I am not sure this topic belongs to..
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MariM
Veteran Member
Posts:2396  
| 17 Nov 2008 11:11 AM |
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If you stack the MODIS bands into one file (using something like Basic Tools ->Layer Stacking), then you can create a z-profile from the display. The plot will show the pixel value (DN) on the y-axis for all bands (each time period across the x-axis).
The key is getting a good layer stack of all the bands. To do this, I would use the MODIS Toolkit, available from our User Contrib section of the ITT VIS website, which will allow you to open and register the MODIS files to a map projection. Once all the files are imported into ENVI and have a map projection, you can use the Layer Stacking tool to combine them into one file.
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Deleted User
New Member
Posts: 
| 17 Nov 2008 11:33 AM |
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many thanks for your quickly response.
I 'll try with your instruction. thank you,Mminari.
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Deleted User
New Member
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| 18 Nov 2008 07:44 AM |
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Hi,
It works well as your menthod. But there is an corresponding question with this.
On the plotting X axis, all the bands are distributed as equal space. However, sometimes the time-series MODIS data are obtained at different time scale.
Do you have suggestion on this problem?
Thanks.
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