scatter plot: tall arrays eating up all the memory

I am working on tone mapping operators in HDR. My question is very simple. I want to scatter plot large arrays on Matlab 2015Ra with computer specs core i5 20GB RAM. Only the scatter plot eats up the whole memory (around 92% of 20GB). I need some suggestion to plot tall arrays. I know Matlab 2018 has binscatter function but I have lower version. Thank you. Sample Code:I am working on tone mapping operators in HDR.