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Questions tagged [frequency]

The rate at which a thing occurs or is found.

The rate at which a thing occurs or is found.

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Meaning of the function numpy.fft.fftfreq

Some days ago I came across this answer about the usage of the FFT In the answer there's a piece of code like this: w = np.fft.fft(data) freqs = np.fft.fftfreq(len(w)) I read about the function fftfreq in the numpy documentation (here) and i found…
Davide Pisanò
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Frequency of values per column in table

What is a good way to get the independent frequency counts of multiple columns using dplyr? I want to go from a table of values: # A tibble: 7 x 4 a b c d 1 1 2 1 3 2 1 2 1 …
tkerwin
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Calculating Bandpower of a Signal in Python

I have to calculate the bandpower of a signal for a certain vector of frequencies in python as a project. In MATLAB it can be done using p = bandpower(pxx,f,'psd') where pxx is Power spectral density vector and f, is a vector of frequencies…
tahsin314
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Table frequency from multiple col and multiple row in R

I am trying to get a frequency table from this dataframe: tmp2 <- structure(list(a1 = c(1L, 0L, 0L), a2 = c(1L, 0L, 1L), a3 = c(0L, 1L, 0L), b1 = c(1L, 0L, 1L), b2 = c(1L, 0L, 0L), b3 = c(0L, 1L, 1L)), …
S12000
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Create a two-mode frequency matrix in R

I have a data frame, which looks something like this: CASENO Var1 Var2 Resp1 Resp2 1 1 0 1 1 2 0 0 0 0 3 1 1 1 1 4 1 1 0 1 5 1 0 …
jj987246
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Overlay density plot excludes histogram values

I want to overlay a density curve to a frequency histogram I have constructed. For the frequency histogram I used aes(y=..counts../40) because 40 is my total sample number. I used aes(y=..density..*0.1) to force the density to be somewhere between 0…
Matias Andina
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NAudio - How to change frequency at runtime (Doppler)

I'd like to know if there is a way to change the frequency(pitch) and volume of the audio while playing in NAudio. I'd like to simulate the Doppler effect. The observer is in the middle and does not move. While the moving object is going to the…
Rok
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Get highest frequency terms from Lucene index

i need to extract terms with highest frequencies from several lucene indexes, to use them for some semantic analysis. So, I want to get maybe top 30 most occuring terms(still did not decide on threshold, i will analyze results) and their…
Julia
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Get maximum supported cpu frequency in linux kernel space

I have found that clk_get_rate() returns the current frequency, but is there any function or way of finding out maximum frequency supported in linux kernel space?
Skull
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How To Detect Sound Frequency on Android?

First of all, I am pretty new to Android. I was doing Arduino before this. And my first objective that I want to achieve is to be able to detect a specific sound frequency or pattern. So, before I can even detect a specific sound frequency, I have…
Syah
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Extract numerical values from zfilter object in python in AudioLazy library

I'm using AudioLazy Library for the extraction of some audio features. The lpc function (Linear Predictive Coding) receives a block in the time domain, and returns the whitening LPC filter (ZFilter) filt = lpc(intensity, order=16) # Analysis…
elviuz
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Getting the most frequent element in a factor in R

I have a set of strings in a R variable, when I check the class, it says it is a factor. eg. mySet<-c("abc","abc","def","abc","def","efg","abc") I want to get the string which occurs the maximum number of times in this set(i.e."abc" in this…
arjun010
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change pitch of multiple audio files with Sox

I am intending to take my entire music collection and change the pitch from the original recorded a=440hz to the more natural sounding/feeling a=432hz. For those of you who are not familiar with this concept, or the "why" for doing this, I highly…
user2946608
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Specify the channel (or frequency) for Wi-Fi scan in Android

I understand that do a Wi-Fi scan in Android is pretty simple. You get a WiFiManager, register a BroadcastReceiver and invoke WiFiManager.startScan(). Then you just need to wait. The problem is I don't want to wait that long. To do this, instead of…
huangcd
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How to get the frequency from PCM data in java - fft

For some reason the frequencies as displaced 391 hz => 1162 440 hz => 2196 493 hz => 2454 I am using this values final int audioFrames= 1024; final float sampleRate= 44100.0f; final int bitsPerRecord= 16; final int channels= 1; final…
Jose Hidalgo
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