Hi, I'm using the Gaussfit procedure to plot a Gaussian to line spectra. However, IDL is picking the wrong peak to plot a Gaussian to. I want to specify that the peak is at 0, (so something like a[1]=0 presumably) but I don't know the other parameters. How can I specify one parameter without specifying them all? On a related note, I also want to plot an absorption Gaussian on top of an emission Gaussian. How would I do that? Thanks