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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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Count the frequency that a value occurs in a dataframe column

I have a dataset category cat a cat b cat a I'd like to be able to return something like (showing unique values and frequency) category freq cat a 2 cat b 1
yoshiserry
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How to count the frequency of the elements in an unordered list?

I need to find the frequency of elements in an unordered list a = [1,1,1,1,2,2,2,2,3,3,4,5,5] output-> b = [4,4,2,1,2] Also I want to remove the duplicates from a a = [1,2,3,4,5]
Bruce
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Relative frequencies / proportions with dplyr

Suppose I want to calculate the proportion of different values within each group. For example, using the mtcars data, how do I calculate the relative frequency of number of gears by am (automatic/manual) in one go with…
jenswirf
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What values are valid in Pandas 'Freq' tags?

I am new to Pandas, and am trying to use date_range. I came across all kinds of good things for freq, like BME and BMS and I would like to be able to quickly look up the proper strings to get what I want. Yesterday I found a nicely formatted table…
sundowner
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Getting the count of unique values in a column in bash

I have tab delimited files with several columns. I want to count the frequency of occurrence of the different values in a column for all the files in a folder and sort them in decreasing order of count (highest count first). How would I accomplish…
sfactor
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Frequency table for a single variable

One last newbie pandas question for the day: How do I generate a table for a single Series? For example: my_series = pandas.Series([1,2,2,3,3,3]) pandas.magical_frequency_function( my_series ) >> { 1 : 1, 2 : 2, 3 : 3 } Lots of…
Abe
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Count frequency of words in a list and sort by frequency

I am using Python 3.3 I need to create two lists, one for the unique words and the other for the frequencies of the word. I have to sort the unique word list based on the frequencies list so that the word with the highest frequency is first in the…
user3088605
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python equivalent of R table

I have a list [[12, 6], [12, 0], [0, 6], [12, 0], [12, 0], [6, 0], [12, 6], [0, 6], [12, 0], [0, 6], [0, 6], [12, 0], [0, 6], [6, 0], [6, 0], [12, 0], [6, 0], [12, 0], [12, 0], [0, 6], [0, 6], [12, 6], [6, 0], [6, 0], [12, 6], [12, 0], [12, 0], [0,…
Donbeo
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Item frequency count in Python

Assume I have a list of words, and I want to find the number of times each word appears in that list. An obvious way to do this is: words = "apple banana apple strawberry banana lemon" uniques = set(words.split()) freqs = [(item,…
Daniyar
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How to get the number of the most frequent value in a column?

I have a data frame and I would like to know how many times a given column has the most frequent value. I try to do it in the following way: items_counts = df['item'].value_counts() max_item = items_counts.max() As a result I get: ValueError:…
Roman
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Getting frequency values from histogram in R

I know how to draw histograms or other frequency/percentage related tables. But now I want to know, how can I get those frequency values in a table to use after the fact. I have a massive dataset, now I draw a histogram with a set binwidth. I want…
MiMi
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How to count how many values per level in a given factor?

I have a data.frame mydf with about 2500 rows. These rows correspond to 69 classes of objects in colum 1 mydf$V1, and I want to count how many rows per object class I have. I can get a factor of these classes with: objectclasses =…
Escher
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How to find most common elements of a list?

Given the following list ['Jellicle', 'Cats', 'are', 'black', 'and', 'white,', 'Jellicle', 'Cats', 'are', 'rather', 'small;', 'Jellicle', 'Cats', 'are', 'merry', 'and', 'bright,', 'And', 'pleasant', 'to', 'hear', 'when', 'they', 'caterwaul.', …
user434180
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Python library for playing fixed-frequency sound

I have a mosquito problem in my house. This wouldn't usually concern a programmers' community; However, I've seen some devices that claim to deter these nasty creatures by playing a 17Khz tone. I would like to do this using my laptop. One method…
Adam Matan
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Android audio FFT to retrieve specific frequency magnitude using audiorecord

I am currently trying to implement some code using Android to detect when a number of specific audio frequency ranges are played through the phone's microphone. I have set up the class using the AudioRecord class: int channel_config =…
user723060
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