BT = (K2) ./ (log((K1 ./ L+ 1)));y = int16(11.289);P = (1.438*10.^-2);Problem comes from this
LST = (BT)./(1 + y(BT))./(P)*(log(Ei));MATLAB: Subscript indices must either be real positive integers or logicals.
faqsubscript indices must either be real positive integers
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Maybe you need to do element-wise multiply for that calculation using the .* operator (with the dot in the front) instead of the matrix multiply operator * (without the dot).
Also, not sure what you expect as a result when dividing by a cell. E.g., this line
LST = (BT)./{1 + (y*(BT)./P)*log(Ei)};Did you mean for those curly braces { } to be parentheses instead ( ) ?
First, the problem is somewhat related to the encoding of your tiff file. The data values are encoded as single-precision numbers, and the background points are encoded as 0xff7fffff in hexadecimal (equal to -3.40282346639e+38, minimum possible number in IEEE754 single-precision floating-point format).
Second, the tiff file only has 1 channel, and have no color information, so you need to create your colormap.
Both problems can be solved by converting the loaded matrix from single to uint16. Note that we are converting the values, not typecasting. Converting to uint16 will convert the background pixels from -3.40282346639e+38 to 0. The elevation values lie in the range [0 - 10000], uint16 is sufficient to hold these values. The integer values will make it an indexed image that can take value from a colormap. Try the following code
[A,R] = readgeoraster('DEM_30s.tif', 'OutputType', 'double');low_single = typecast(uint8([255 255 127 255]), 'single');mask = low_single==A;A = A - min(A(~mask), [], 'all');% creating colormap changing from white to brown as shown in image in the question
brown_color = [0.8 0.2 0.1];light_brown = [0.95 0.9 0.8];t = linspace(0, 1, max(A,[],'all'))';cmap = t.*brown_color + (1-t).*white;gs = geoshow(A, cmap, R);gs.CData(repmat(mask,1,1,3)) = 255;
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