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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.

2858 questions
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How to get top K elements from count-min-sketch?

I'm reading how the probabilistic data structure count-min-sketch is used in finding the top k elements in a data stream. But I cannot seem to wrap my head around the step where we maintain a heap to get our final answer. The problem: We have a…
scabbage
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How can I use the `td` command from the `tempdisagg` package to disaggregate monthly data into daily data frequency?

I have a monthly frequency data which I am trying to disaggregate into a daily frequency data. So I use the td command from the tempdisagg package in R using the code below: dat=ts(data[,2]) result=td(dat~1, conversion = "average", to = "day",…
Eric
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The axis argument to unique is not supported for dtype object

I am trying to get unique counts column-wise but my array has categorical variables (dtype object) val, count = np.unique(x, axis=1, return_counts=True) Though I am getting an error like this: TypeError: The axis argument to unique is not supported…
Abhijay Ghildyal
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Frequency detection from a sound file

What I am trying to achieve is the following: I need the frequency values of a sound file (.wav) for analysis. I know a lot of programs will give a visual graph (spectrogram) of the values but I need to raw data. I know this can be done with FFT and…
Mieke Zwart
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R: frequency with group by ID

I have a data frame like this: ID Cont 1 a 1 a 1 b 2 a 2 c 2 d I need to report the frequence of "Cont" by ID. The output should be ID Cont Freq 1 a 2 1 b 1 2 a 1 2 c 1 2 d 1
Tyu1990
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How to get only audio frequency and decibles from FFTBasedSpectrumAnalyzer project?

I'm using FFTBasedSpectrumAnalyzer. I'm new to FFT. How do I continuously listen to external audio and calculate only frequency and decibels. Are there any other simple libraries where I can get frequency and decibels continuously.
Anirudh
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Cutting of unused frequencies in specgram matplotlib

I have a signal with sampling rate 16e3, its frequency range is from 125 to 1000 Hz. So if i plot a specgram i get a pretty small colorrange because of all the unused frequencys. ive tried to fix it with setting ax limits but that does not work. is…
Masti Tafri
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MySQL SELECT most frequent by group

How do I get the most frequently occurring category for each tag in MySQL? Ideally, I would want to simulate an aggregate function that would calculate the mode of a column. SELECT t.tag , s.category FROM tags t LEFT JOIN stuff s USING (id)…
Stephen Fuhry
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Include zero frequencies in frequency table for Likert data

I have a dataset with responses to a Likert item on a 9pt scale. I would like to create a frequency table (and barplot) of the data but some values on the scale never occur in my dataset, so table() removes that value from the frequency table. I…
ThomasH
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Alternative to Scipy mode function in Numpy?

Is there another way in numpy to realize scipy.stats.mode function to get the most frequent values in ndarrays along axis?(without importing other modules) i.e. import numpy as np from scipy.stats import mode a = np.array([[[ 0, 1, 2, 3, 4], …
oops
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Convert RGB to light frequency

Is it possible to obtain the light frequency of a colour from a RGB representation? I've found the opposite process [1] but I don't know if it's possible this way. [1] http://www.fourmilab.ch/documents/specrend/
user1031431
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Algorithm to determine the effective "phase difference" between two signals with different frequencies?

The quick version: What algorithm could I use to determine the "phase difference" between two square wave signals with different frequencies, if the only information that I have is the time at which each rising edge occurs? The detailed version:…
e.James
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Audio sample frequency rely on channels?

If you have audio encoded at 44100Hz that means you have 44100 samples per second. Does this mean 44100 samples/sec for a channel, or for all channels? For example if a song is stereo and encoded at 44100Hz, are there 44100 sample/sec for both…
goocreations
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How to create a wordcloud according to frequencies in a pandas dataframe

I have to plot a wordcloud. 'tweets.csv' is a Pandas dataframe which has a column named 'text'. The plotted graph hasn't been based on the most common words, tough. How can the words sizes be linked to their frequencies in dataframe? text =…
vivape
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Relative frequency histogram in R, ggplot

I can draw relative frequency histogram in R, using lattice package: a <- runif(100) library(lattice) histogram(a) I want to get the same graph in ggplot. I tried dt <- data.frame(a) ggplot(dt, aes(x = a)) + geom_bar(aes(y = ..prop..))+ …
neringab
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