Plots with very small y values

asanture · Post by **asanture** » Thu Jan 04, 2007 10:56 am

Hi there,
I've been using DPlotJr to plot likelihoods for different configurations across iterations (ie using _AddData each iteration). When I have "reasonable" likelihoods of the order 1xe^-40 DPlot plots beautifully, but with very small likelihoods of the order 1xE^-80 DPlot seems to read every y value as zero and plots accordingly. Can you please tell me the minimum y value that DPlot will accept?
Thanks for your help!
Anna

Post by **DPlotAdmin** » Thu Jan 04, 2007 2:33 pm

You should use DPlot_AddData8 rather than DPlot_AddData, and use Double for your data rather than Single. It is actually your program that is truncating the data, not DPlot Jr or DPLOTLIB.DLL. The range in magnitudes for 4-byte floating point numbers (VB's Single) is ~1.175E-38 to ~3.402E+38. For 8-byte floats (Double) the range is ~2.225E-308 to ~1.798E+308.