Skip to main content

plotting - Graphical representation of a moving sound source


Some explanation since I have got a specific and another more open-ended question: I used two microphones in a 90° arrangement (see picture below) to capture sound from a source moving around the room in a circular /elliptical fashion. The intention is to get an idea about directional hearing. (A second measurement with a KEMAR dummy-head was done as well).


arrangement microphone arrangement


I saved the measured data as .wav (48kHz) and imported the .wav file into Mathematica. (The .wav- file can be found here). That made a pretty long list - approximately 900000 entries per channel. Hence I used



 dropfunction[data_, n_] := 
Table[Nest[Drop[#, {1, -1, 2}] &, data[[i]], n], {i, 1, 2}]

to reduce the resolution. I found by hearing/looking at ListLinePlot that n = 7 is a good catch. That leaves around 7000 entries per channel.


Here comes my first and very specific question: I plotted the absolute values of my list in a fashion like:


ListLinePlot[Abs@data[[1]], -Abs[data[2]]]

and got:


left vs. right channel


with left and right channel clearly divided along the x-axis.



Question 1: Is there a possibility to flip the plot in such a way that x-axis becomes the y-axis? (So that for instance the "loudness" of the right channel is on the right hand side). I tried PairedBarChart actually gives the kind of representation I wish, but It is just not suitable for my data.


Question 2: Does anybody else have a great idea how to graphically represent my data? I tried plotting the difference of the absolute values of both channels to get a graph showing which channel is currently louder at the positions in time/on my elliptical path. With some lowpass-filtering I got:


enter image description here




Comments

Popular posts from this blog

front end - keyboard shortcut to invoke Insert new matrix

I frequently need to type in some matrices, and the menu command Insert > Table/Matrix > New... allows matrices with lines drawn between columns and rows, which is very helpful. I would like to make a keyboard shortcut for it, but cannot find the relevant frontend token command (4209405) for it. Since the FullForm[] and InputForm[] of matrices with lines drawn between rows and columns is the same as those without lines, it's hard to do this via 3rd party system-wide text expanders (e.g. autohotkey or atext on mac). How does one assign a keyboard shortcut for the menu item Insert > Table/Matrix > New... , preferably using only mathematica? Thanks! Answer In the MenuSetup.tr (for linux located in the $InstallationDirectory/SystemFiles/FrontEnd/TextResources/X/ directory), I changed the line MenuItem["&New...", "CreateGridBoxDialog"] to read MenuItem["&New...", "CreateGridBoxDialog", MenuKey["m", Modifiers-...

How to thread a list

I have data in format data = {{a1, a2}, {b1, b2}, {c1, c2}, {d1, d2}} Tableform: I want to thread it to : tdata = {{{a1, b1}, {a2, b2}}, {{a1, c1}, {a2, c2}}, {{a1, d1}, {a2, d2}}} Tableform: And I would like to do better then pseudofunction[n_] := Transpose[{data2[[1]], data2[[n]]}]; SetAttributes[pseudofunction, Listable]; Range[2, 4] // pseudofunction Here is my benchmark data, where data3 is normal sample of real data. data3 = Drop[ExcelWorkBook[[Column1 ;; Column4]], None, 1]; data2 = {a #, b #, c #, d #} & /@ Range[1, 10^5]; data = RandomReal[{0, 1}, {10^6, 4}]; Here is my benchmark code kptnw[list_] := Transpose[{Table[First@#, {Length@# - 1}], Rest@#}, {3, 1, 2}] &@list kptnw2[list_] := Transpose[{ConstantArray[First@#, Length@# - 1], Rest@#}, {3, 1, 2}] &@list OleksandrR[list_] := Flatten[Outer[List, List@First[list], Rest[list], 1], {{2}, {1, 4}}] paradox2[list_] := Partition[Riffle[list[[1]], #], 2] & /@ Drop[list, 1] RM[list_] := FoldList[Transpose[{First@li...

dynamic - How can I make a clickable ArrayPlot that returns input?

I would like to create a dynamic ArrayPlot so that the rectangles, when clicked, provide the input. Can I use ArrayPlot for this? Or is there something else I should have to use? Answer ArrayPlot is much more than just a simple array like Grid : it represents a ranged 2D dataset, and its visualization can be finetuned by options like DataReversed and DataRange . These features make it quite complicated to reproduce the same layout and order with Grid . Here I offer AnnotatedArrayPlot which comes in handy when your dataset is more than just a flat 2D array. The dynamic interface allows highlighting individual cells and possibly interacting with them. AnnotatedArrayPlot works the same way as ArrayPlot and accepts the same options plus Enabled , HighlightCoordinates , HighlightStyle and HighlightElementFunction . data = {{Missing["HasSomeMoreData"], GrayLevel[ 1], {RGBColor[0, 1, 1], RGBColor[0, 0, 1], GrayLevel[1]}, RGBColor[0, 1, 0]}, {GrayLevel[0], GrayLevel...