Which Software to Analyze Logged data? - Page 1
Forum section: electronics / testgear

author: sirtet
author_rank: Contributor
timestamp: August 29, 2019, 12:25:42 pm
content: Not sure if this is the right place, but i guess Test Equipment Software counts...I am looking for something like a "Software Oscillloscope", to analyze captured data like I, U, P etc.Specifically i want to zoom through some VA captures from 121GW, measure some times and calculate mWh/mAh etc.Currently i look at graphs i create in LibreOffice, but there i can't easily zoom in/out and move forth/back etc.I guess there are tools for that around, but my google-foo was not good enough to bring something up.But, i guess some interesting hints can be obtained here?

author: PartialDischarge
author_rank: Super Contributor
timestamp: August 29, 2019, 12:32:32 pm
content: Octave, the free version of Matlab is the right software for vector data manipulation/plotting

author: nctnico
author_rank: Super Contributor
timestamp: August 29, 2019, 01:03:58 pm
content: Yes, Gnu Octave is what I'm thinking too. Or scripting in Python or Lua.

author: sirtet
author_rank: Contributor
timestamp: August 29, 2019, 01:28:24 pm
content: Thanks.But Octave reads like much more than what i look for, i was thinking of something that really behaves just more like a Scope,letting me zoom through a plot and allow measuring/value reading on both axes.

author: mark03
author_rank: Frequent Contributor
timestamp: August 29, 2019, 07:46:23 pm
content: Quote from: MasterTech on August 29, 2019, 12:32:32 pmOctave was the correct answer 10-20 years ago. Today the correct answer is Python with NumPy/SciPy. I am fluent in MATLAB but would not want to go back at this point (and Octave is basically the same thing, except not as polished).YMMV of courseWhat I would find useful is some generic software with a great UI for interactive time-series exploration and analysis. Perhaps that is what the OP was asking for. Unfortunately I'm not aware of any.

author: thm_w
author_rank: Super Contributor
timestamp: August 30, 2019, 11:38:37 pm
content: Yes OP is looking for something simple with pan and zoom (ala salea), not to create a static graphical plot. You can fudge some interactiveness with octave/matlab but nothing I see in terms of examples looks very good.plotly or bokeh might be options:https://plot.ly/create/#/(web)https://towardsdatascience.com/introduction-to-interactive-time-series-visualizations-with-plotly-in-python-d3219eb7a7af(python)https://realpython.com/python-data-visualization-bokeh/(python)https://apexcharts.com/javascript-chart-demos/line-charts/brush-chart/(web brush style chart, just an idea)Where this is done best is on web based or mobile platforms. So it might take some effort to translate it into some kind of 'standalone' app. However, once the initial setup is done it would be possible to have a simple workflow: drag and drop CSV onto a page then pan around the data. Maybe you can write something for the 121GW.Standalone apps, not looking great:http://www.datplot.com/http://www.samplesw.com/en/csw.htmlcant even download it?There are a surprising amount of serial port plotting tools though:https://arduino.stackexchange.com/questions/1180/serial-data-plotting-programs

author: PartialDischarge
author_rank: Super Contributor
timestamp: August 31, 2019, 07:18:38 pm
content: Quote from: thm_w on August 30, 2019, 11:38:37 pmOctave creates an interactive plot window with pan/zoom with selectable grid spacing and much more, it is notfudgednor static, but right there into the plot window. And I don't know what can be easier than:load a.txtload b.txtplot (A.*B)grid ontitle ("A * B");

author: SilverSolder
author_rank: Super Contributor
timestamp: August 31, 2019, 08:20:39 pm
content: As a graduate of the University of Youtube, with no Matlab or Octave experience, I downloaded Octave last week to try FIR, IIR filter designs.I found it reasonably easy to use, it is obviously a very deep application that can do a lot, but it doesn't have a "Photoshop style" learning curve of an overwhelming user interface.The usual open source weird bugs or "unpolished" feeling was definitely there, e.g., saving a graph as a Windows metafile saved an empty file, whereas saving as PDF, PNG, SVG all worked as expected... overall, though, Octave did work reliably with everything I tried.I haven't tried graphing random data from a file, but it seems to me (a complete n00b) that it might be a powerful tool for this, since you can run filters and scale the data pretty much any way you want, not to mention being able to run FFT analysis and other advanced things from the same environment.It all comes down to how easy (or hard) it is to load the data into the application, which is something I haven't tried at all. Once it is in there, it is definitely easy to graph it....Later...I was able to load a sample text file that I created in Excel, which contained two columns of numbers (tab separated).It was possible to load the file into an Octave variable and do a plot of column 1 vs. column 2 of the file.Here is what I did - there are probably better ways, but it worked:%Open the data filefid = fopen (C:\tab-delimited-sample-file.txt');%The format string has a %d for each integer to be picked out of a line. Delimiter set to TAB '\t'. 1 header line skipped.V = textscan (fid, '%d %d', 'delimiter', '\t', 'headerlines', 1);%Basic plot of col 1 vs. col 2plot(V{1}, V{2});

author: sirtet
author_rank: Contributor
timestamp: September 02, 2019, 10:55:35 pm
content: Thanks.That stuff looked too daunting, so i googled some more for "open source oscilloscope software" etc.and herehttps://windowsreport.com/oscilloscope-software-pc-laptop/Saw WaveForms by Digilent mentioned.It has a CSV import function, got my data in and it seems to do what i want with it.But i need to experiment some more.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 02, 2019, 11:25:17 pm
content: The Digilent software looks good. - probably even better if you have a Digilent scope to go with it!I stumbled over this one, looks really straightforward:http://www.datplot.combut haven't tested it.

author: thm_w
author_rank: Super Contributor
timestamp: September 03, 2019, 11:53:02 pm
content: Quote from: MasterTech on August 31, 2019, 07:18:38 pmThank you, tried:x = dlmread('test.csv',',',2,0)plot (x)Works very well and a hell of a lot better than matlab, but, its not as simple as it could be. You have to click the 'pan' button to pan, then switch back to the 'zoom in' button to zoom.A simpler interface would be to add: 'ctrl+scroll' for zooming, combine that with the existing shift + scroll would be nice.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 04, 2019, 12:08:18 pm
content: Quote from: thm_w on September 03, 2019, 11:53:02 pmThat was very simple, thank you.Once X is loaded, I then used this to plot column 1 against column 2 - is this the easiest ("right") way? :plot(x(:,1), x(:,2))Quote from: thm_w on September 03, 2019, 11:53:02 pmYou can zoom with the mouse wheel while in "pan/zoom" mode (Octave 5.1).

author: thm_w
author_rank: Super Contributor
timestamp: September 04, 2019, 09:02:40 pm
content: Quote from: SilverSolder on September 04, 2019, 12:08:18 pmThat looks good.QuoteI only saw a 'pan' mode and mouse wheel will move the plot up/down. Then have to switch to zoom mode.

author: SilverSolder
author_rank: Super Contributor
timestamp: September 05, 2019, 01:06:45 am
content: Quote from: thm_w on September 04, 2019, 09:02:40 pmFrom what I've been able to glean, you can change the entire graphics system in Octave (I see three different ones here), and you get different plot windows with different capabilities with each. Nothing like freedom of choice, right? Below are the three types of plot window that Octave can display.QT (default), no scroll wheel zoom:Gnuplot (does support scroll wheel zoom):Fltk (also supports scroll wheel zoom):To change between the different modes, do one of these before the plot command:graphics_toolkit ("gnuplot")graphics_toolkit("qt")graphics_toolkit ("fltk")You may have to close any figures that are already open. (e.g. issue aclose allcommand) before issuing the toolkit command.