How to write a random array (with no spatial reference) to geotiff format? - arrays

Question

The following MATLAB script generates random locations within a 300x400 array and codes those locations with values from 1-12. How can I convert this non-spatial array to a geotiff? I hope to use the geotiff output to perform some trial analyses. Any projected coordinate system (e.g. UTM) would do for this analysis.
I have tried using geotiffwrite() without success using the following implementation:
out = geotiffwrite('C:\path\to\file\test.tif', m)
Which yields the following error:
>> test
Error using geotiffwrite
Too many output arguments.
EDIT:
The main problem I am encountering is a lack of inputs into the geotiffwrite() function. I am unsure how to deal with this problem. For example, I have no A or R variable because the array has no spatial reference. As long as each pixel is georeferenced somewhere, I do not care what the spatial reference is. The purpose of this is to create a sample dataset that I can experiment with using MATLAB spatial functions.
% Generate a totally black image to start with.
m = zeros(300, 400, 'uint8');
% Generate 1000 random locations.
numRandom = 1000;
linearIndices = randi(numel(m), 1, numRandom);
% Set those locations to be "white".
m(linearIndices) = randi(12, [numel(linearIndices) 1]);
% Display it. Random locations will appear white.
image(m);
colormap(gray);

Answer 1

I believe your question has a very simple answer. Skip the out-variable when you call geotiffwrite. That is, use:
geotiffwrite('C:\path\to\file\test.tif', m)
Instead of
out = geotiffwrite('C:\path\to\file\test.tif', m)
This is example of a working code using geotiffwrite, taken from the documentation. As you can see, there is no output variable there:
basename = 'boston_ovr';
imagefile = [basename '.jpg'];
RGB = imread(imagefile);
worldfile = getworldfilename(imagefile);
R = worldfileread(worldfile, 'geographic', size(RGB));
filename = [basename '.tif'];
geotiffwrite(filename, RGB, R)
figure
usamap(RGB, R)
geoshow(filename)
Update:
According to the documentation, you need at least 3 input parameters. The correct syntax is:
geotiffwrite(filename,A,R)
geotiffwrite(filename,X,cmap,R)
geotiffwrite(...,Name,Value)
From documentation:
geotiffwrite(filename,A,R) writes a georeferenced image or data grid,
A, spatially referenced by R, into an output file, filename.
Please visit this link to see how to use the function.