frequency

问题 I'm very new to Cuda, I've read a few chapters from books and read a lot of tutorials online. I have made my own implementations on vector addition and multiplication. I would like to move a little further, so let's say we want to implement a function that takes as an input a sorted array of integers. Our goal is to find the frequencies of each integer that is in the array. Sequentially we could scan the array one time in order to produce the output. The time complexity would be O(n) . Since

问题 What I am trying to do is to analyse the frequency of the letters in a text. As an example, I will use here a small sentence, but all that is thought to analyse huge texts (so it's better to be efficient). Well, I have the following text: test = "quatre jutges dun jutjat mengen fetge dun penjat" Then I created a function which counts the frequencies def create_dictionary2(txt): dictionary = {} i=0 for x in set(txt): dictionary[x] = txt.count(x)/len(txt) return dictionary And then import numpy

问题 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..))+ scale_y_continuous(labels=percent) but it doesn't work like that. What I should change in the code? Calculating relative frequency before graph is not an option for me. 回答1: You want a histogram, not a barplot, so: ggplot(dt, aes(x = a)) + geom_histogram(aes

问题 This question already has answers here : Apply several summary functions on several variables by group in one call (7 answers) Closed 4 years ago . I have a data.frame like this (example): product protein fat starch aaa 40 5 10 bbb 50 6 8 ccc 12 50 4 and I want to ask for a summary of this values (min,max,1stQ, 3rdQ..). When I run: aggregate(protein~product,summary,data=DATA4, na.rm = TRUE) I have this... product protein.Min. protein.1st Qu. protein.Median protein.Mean protein.3rd Qu. protein

问题 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 that it returns an array with the following content: f = [0, 1, ..., n/2-1, -n/2, ..., -1] / (d*n) if n is even f = [0, 1, ..., (n-1)/2, -(n-1)/2, ..., -1] / (d*n) if n is odd In my case, the d var is equal to 1 and n is an even number. So my

问题 I have two columns titled "Company" and "Department", example below. The third column is what I would like to create, but I am unsure how. I want the third column to show the number of departments for a given company, and only show that number in the first reference to the company. 回答1: Try this in D2 and fill down. =IF(COUNTIF(A$2:A2, A2)=1, SUMPRODUCT((A$2:A$999=A2)/(COUNTIFS(B$2:B$999, B$2:B$999&"", A$2:A$999, A2)+(A$2:A$999<>A2))), "") 回答2: If you create a helper column in Column C that

问题 I have two columns titled "Company" and "Department", example below. The third column is what I would like to create, but I am unsure how. I want the third column to show the number of departments for a given company, and only show that number in the first reference to the company. 回答1: Try this in D2 and fill down. =IF(COUNTIF(A$2:A2, A2)=1, SUMPRODUCT((A$2:A$999=A2)/(COUNTIFS(B$2:B$999, B$2:B$999&"", A$2:A$999, A2)+(A$2:A$999<>A2))), "") 回答2: If you create a helper column in Column C that

问题 I would like to create a table that lists the frequency of each variables frequencies. For example, a data set with 100 rows and 4 variables: ID, A, B, and C. What I'm looking for would be like this: Freqs| ID A B C ---------------------------- 1 | 100 20 15 10 2 | 0 40 35 0 3 | 0 0 5 30 Since there are 100 unique IDs, there will be a frequency of 100 frequencies of 1 from the original data. edit for clarification: If you did a proc freq on the original data, you would get a frequency of 1

问题 I'm looking for a way to count the frequency of each element in a vector. ex <- c(2,2,2,3,4,5) Desired outcome: [1] 3 3 3 1 1 1 Is there a simple command for this? 回答1: rep(table(ex), table(ex)) # 2 2 2 3 4 5 # 3 3 3 1 1 1 If you don't want the labels you can wrap in as.vector() as.vector(rep(table(ex), table(ex))) # [1] 3 3 3 1 1 1 I'll add (because it seems related somehow) that if you only wanted consecutive values, you could use rle instead of table : ex2 = c(2, 2, 2, 3, 4, 2, 2, 3, 4, 4)

问题 I would like to convert my daily dataframe of stock data to a quarterly one. However, using resample did not work, because I have a multi index, so I would like my final quarterly dataframe to still contain the individual stocks (resample just summarizes all of them): import pandas as pd dict1 = [ {'ticker':'jpm','date': '2016-11-27','returns': 0.2}, {'ticker':'jpm','date': '2016-11-28','returns': 0.2}, {'ticker':'ge','date': '2016-11-27','returns': 0.2}, {'ticker':'ge','date': '2016-11-28',