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midraed / water

R package to calculate surface energy balance models
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Error in calcAnchors(image = image.TOAr, Ts = Ts, LAI = LAI, plots = T, : Not enough pixels with the conditions for anchor pixels. I found 0 cold pixels and 0 hot pixels. #54

Open Omar87senjar opened 1 year ago

Omar87senjar commented 1 year ago

I have challenges with the Energy Balance calculation of the water package, following the example code found on: https://cran.rproject.org/web/packages/water/vignettes/Landsat8.html. Using my own data, I read my original landsat image and the surface reflectance image with my area of interests (aoi). But, I get the following error when I use this code.

Energy.Balance <- METRIC.EB(image.DN = image_band, image.SR = image_SR_band, plain = TRUE, aoi = aoi, n = 5, WeatherStation = WeatherStation, ETp.coef = 1.2, sat = "L8", alb.coeff = "Olmedo", LST.method = "SW", LAI.method = "metric2010", thermalband=image.DN$thermal.low, Z.om.ws = 0.03, anchors.method = "flexible", MTL = MTLfile)

Error in calcAnchors(image = image.TOAr, Ts = Ts, LAI = LAI, plots = T, : Not enough pixels with the conditions for anchor pixels. I found 0 cold pixels and 0 hot pixels. In addition: Warning messages: 1: PROJ support is provided by the sf and terra packages among others 2: In calcAnchors(image = image.TOAr, Ts = Ts, LAI = LAI, plots = T, : anchor method names has changed. Old names (CITRA-MCBx) are deprecated. Options now include 'best', 'random' and 'flexible' 3: In max(Ts[albedo >= 0.13 & albedo <= 0.15 & NDVI >= 0.1 & NDVI <= : no non-missing arguments to max; returning -Inf

raushal1 commented 1 year ago

I also ran into a similar problem. Mine says, "found 0 cold pixels and 14 hot pixels". Please let me know if you figured it out somehow. image

raushal1 commented 1 year ago

@midraed Can you please take a look at this, sir? What do you think might have caused this error?

Omar87senjar commented 1 year ago

if i solve the problem, i will inform you.

raushal1 commented 1 year ago

Thanks a lot. Also, sir, is there a way to get in touch with you? Maybe your linkedin? I would like to discuss some issues that I am facing with the code and see if you are facing similar issues?

Omar87senjar commented 1 year ago

Ok no problem. https://www.linkedin.com/in/omar-alsenjar-6431aaa0/. You can send me message to my account. With all respect

ishwar97 commented 1 year ago

Hey @Omar87senjar and @raushal1, I also faced similar issue when I was working with water package. It is necessary for algorithm to find at least one hot and cold pixel per scene to run successfully. Sometimes, it is not possible to find one pixel each for hot and cold conditions as per the criteria cited in https://journal.r-project.org/archive/2016/RJ-2016-051/RJ-2016-051.pdf. I found a work around to it by changing the script of function calcAnchors and manipulating the flexibility limits to find at least one hot and cold pixel. Hope this helps!