summary | 易学教程

How to get the sum of each four rows of a matrix in R

阅读更多关于 How to get the sum of each four rows of a matrix in R

问题 I have a 4n by m matrix (sums at 7.5 min intervals for a year). I would like to transform these to 30 min sums, e.g. convert a 70080 x 1 to a 17520 matrix. What is the most computationally efficient way to do this? More specifics: here is an example (shortened to one day instead of one year) library(lubridate) start.date <- ymd_hms("2009-01-01 00:00:00") n.seconds <- 192 # one day in seconds time <- start.date + c(seq(n.seconds) - 1) * seconds(450) test.data <- data.frame(time = time,

How to get a regression summary in Python scikit like R does?

阅读更多关于 How to get a regression summary in Python scikit like R does?

问题 As an R user, I wanted to also get up to speed on scikit. Creating a linear regression model(s) is fine, but can't seem to find a reasonable way to get a standard summary of regression output. Code example: # Linear Regression import numpy as np from sklearn import datasets from sklearn.linear_model import LinearRegression # Load the diabetes datasets dataset = datasets.load_diabetes() # Fit a linear regression model to the data model = LinearRegression() model.fit(dataset.data, dataset

Obtaining Separate Summary Statistics by Categorical Variable with Stargazer Package

阅读更多关于 Obtaining Separate Summary Statistics by Categorical Variable with Stargazer Package

I would like to use stargazer to produce summary statistics for each category of a grouping variable. I could do it in separate tables, but I'd like it all in one – if that is not unreasonably challenging for this package. For example library(stargazer) stargazer(ToothGrowth, type = "text") #> #> ========================================= #> Statistic N Mean St. Dev. Min Max #> ----------------------------------------- #> len 60 18.813 7.649 4.200 33.900 #> dose 60 1.167 0.629 0.500 2.000 #> ----------------------------------------- provides summery statistics for the continues variables in

How to use several summary collections in Tensorflow?

阅读更多关于 How to use several summary collections in Tensorflow?

问题 I have 2 distinctive groups of summaries. One is collected once per batch another one is collected once per epoch. How can I use merge_all_summaries(key='???') to collect summaries in this two groups separately? Doing it manually is always an option but there seems to be a better way. Illustration of how i think it should work: # once per batch tf.scalar_summary("loss", graph.loss) tf.scalar_summary("batch_acc", batch_accuracy) # once per epoch gradients = tf.gradients(graph.loss, [W, D]) tf

How to analyze a JMeter summary report?

阅读更多关于 How to analyze a JMeter summary report?

问题 I get the following result when I run a load test. Can any one help me to read the report? the number of thread = '500 ' ramp up period = '1' Sample = '500' Avg = '20917' min = '820' max = '48158' Std Deviation = '10563.178194669255' Error % = '0.046' throughput = '10.375381295262601' KB/Sec = `247.05023046315702` Avg. Bytes = '24382.664' 回答1: Short explanation looks like: Sample - number of requests sent Avg - an Arithmetic mean for all responses (sum of all times / count) Minimal response

Summary statistics by two or more factor variables?

阅读更多关于 Summary statistics by two or more factor variables?

问题 This is best illustrated with an example str(mtcars) mtcars$gear <- factor(mtcars$gear, labels=c("three","four","five")) mtcars$cyl <- factor(mtcars$cyl, labels=c("four","six","eight")) mtcars$am <- factor(mtcars$am, labels=c("manual","auto") str(mtcars) tapply(mtcars$mpg, mtcars$gear, sum) That gives me the summed mpg per gear. But say I wanted a 3x3 table with gear across the top and cyl down the side, and 9 cells with the bivariate sums in, how would I get that 'smartly'. I could go.

Java Data Structures Reference

阅读更多关于 Java Data Structures Reference

问题 Can anyone give me references of a web site containing a summary of the main Java data structures, and their respective complexity in time (for some given operations like add, find, remove), e.g. Hashtable s are O(1) for finding, while LinkedList s are O(n). Some details like memory usage would be nice too. This would be really helpful for thinking in data structures for algorithms. 回答1: Is there a reason to think that Java's implementation is different (in terms of complexity) than a generic

Details and summary tag compatibility issues

阅读更多关于 Details and summary tag compatibility issues

How do you get the details and summary tag for HTML5 to work on all browsers? I can get the details and summary tag to work with google chrome but i can't get it to work with any other browser. This is an old question, but there is still limited browser support for the details and summary tags. One blog post that I found to be useful was this: http://blog.teamtreehouse.com/use-details-summary-elements . It uses jquery for backward compatibility. I use this to get it to work on all non-supporting browsers: if(this.parentElement.getAttribute('open')!='open') this.parentElement.setAttribute('open

How to Sum multiple lines in sql

阅读更多关于 How to Sum multiple lines in sql

I have multiple lines of data all sharing the same Company id. Is there a way to 'sum' all the amounts to give me one line of data per company id using SQL Server Management Studio 2005? For example I currently have the below data...... Company_Name Company_ID Amount Company 6 10024 120 Company 6 10024 569 Company 6 10024 53 Company 6 10024 100 Company 6 10024 564 Company 7 10638 9500 Company 7 10638 105 Company 7 10638 624 What i would like to try and get is....... Company_ Name Company_ID Amount Company 6 10024 1406 Company 7 10638 10229 Is there a way of doing this? Any advice pointing me

dplyr summarize with subtotals

阅读更多关于 dplyr summarize with subtotals

One of the great things about pivot tables in excel is that they provide subtotals automatically. First, I would like to know if there is anything already created within dplyr that can accomplish this. If not, what is the easiest way to achieve it? In the example below, I show the mean displacement by number of cylinders and carburetors. For each group of cylinders (4,6,8), I'd like to see the mean displacement for the group (or total displacement, or any other summary statistic). library(dplyr) mtcars %>% group_by(cyl,carb) %>% summarize(mean(disp)) cyl carb mean(disp) 1 4 1 91.38 2 4 2 116