Forum Replies Created
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Does this help?
in reply to: turn off autosave?Try to go into the Terminal and do
/Applications/DataGraph.app/Contents/MacOS/DataGraph
See if anything is reported back. What you are doing is to launch DataGraph with the standard output going to the terminal rather than some log file accessible through the Console appliation.
in reply to: Beta crashes on startI disabled dgraphconnect a few months ago. The main reason is that in order to work it needs to listen in on a port. But that port is just a local port, not a network port.
I enabled this again in the latest beta (just uploaded), and going forward I will add it as an option in the preference panel. The default will be to not enable it, but you can turn that on, and the dgraphconnect will tell you to do so.
in reply to: dgraphconnect for App Store users?This has been addressed in the beta. You can specify that you need an exact match, so 0 will be converted to NaN and 100 will not be converted to 1NaNNaN
in reply to: Find&Replace IntegersIn the axis setting you can go into Format = Engineering an select the n,mu,m,k,M,G,T option.
in reply to: How to use nµm kMTG to format an axis?In the online examples, search for “function with summation”. This shows how to evaluate a power series at a list of x values.
in reply to: Displaying A Fourier SeriesI will work on a snooze functionality.
When you quit without closing the windows and open a new version the windows will re-open.
in reply to: “Skip this version” for beta usersI uploaded a new version this morning.
For the Mac App store version, go to DataGraph->Account Info and set up an account. That should automatically register the machine you have so that you can run the beta version.
It both fixes the issue you had and adds a check box to compute smooth contours.
David
in reply to: Scalar field in DG 5.0This is a bug and strange that it wasn’t found earlier.
Will be fixed in the next beta which should be out soon.
in reply to: Scalar field in DG 5.0Fourier Series are a little bit tricky to do right. There is the DFT that maps a list of N values to N complex values. But some questions what you are looking for here.
Q: Is the number of data points a power of 2, i.e. 512,1024 etc. If N is large and a prime this is very slow, to the point of being considered an input error.
Q: Are you interested in the magnitude of the values, often called the spectrum. The N values you get back from the raw DFT really only have N/2 complex values since you hand in real numbers. And as you get closer to the N/2 index the values are inaccurate if you assume that the inital N values were sampling a function that you want the FS for.
Q: What comes out is technically amplitudes of standing frequencies in the domain. And technically if you have a domain from [2,3] and 100 values that means you have values at 2,2.01,…2.99, i.e. the value at 3 is assumed to be the same as the value at 2 and not repeated in the list. If it was you really should have 513,1025 values etc so that the signal to the DFT has 512,1024 etc. It isn’t that slow to handle 100 values, but large Mersenne prime numbers will be very slow (such as 524287).
Where this would fit in is in a new mechanism similar to the Plot Action column. That column uses a x,y pair of columns and returns a single column. The Fourier Series would take in a single column and return another column. Let’s call this a Column Action for now. The function evaluation would fit naturally into this, and some smoothing options would too. The answer to the above questions would help in fleshing out this functionality.
in reply to: Displaying A Fourier Series