I want to graph the data to make reports, and also logging, also measure RMS, frequency, put cursors to calculate time or voltage offsets.
For reports, write all your code in a script file and then click on the publish tab, it will give many options to generate a nice report.
Again, with a script you can loop the readWaveform/getWaveform function.
For RMS values, you can just execute: rms(data)
For finding the frequency, there's no specific function to find a "trigger". So there are two ways to find the frequency: Write your own code to find the zero crossings, however this will usually fail as is the data is non-periodic or contains more than a single tone, the reported frequency may not be accurate. Second option would be to utilise the fft and findpeaks function (which I would recommend using).
As for using cursors, there are some available in the plot window. It is the 10th icon in the plot toolbar, named "Data Cursor".
I can't make a comment on how fast GPIB is as I have never used it. (Only used LXI ).
When you change scale, you need to divide by a different value.