Tag: statistical computing

Interview Tobias Verbeke Open Analytics #rstats #startups

Here is an interview with Tobias Verbeke, Managing Director of Open Analytics (http://www.openanalytics.eu/). Open Analytics is doing cutting edge work with R in the enterprise software space.
Ajay- Describe your career journey including your involvement with Open Source and R. What things enticed you to try R?

Tobias- I discovered the free software foundation while still at university and spent wonderful evenings configuring my GNU/Linux system and reading RMS essays. For the statistics classes proprietary software was proposed and that was obviously not an option, so I started tackling all problems using R which was at the time (around 2000) still an underdog together with pspp (a command-line SPSS clone) and xlispstat. From that moment on, I decided that R was the hammer and all problems to be solved were nails 😉 In my early career I worked as a statistician / data miner for a general consulting company which gave me the opportunity to bring R into Fortune 500 companies and learn what was needed to support its use in an enterprise context. In 2008 I founded Open Analytics to turn these lessons into practice and we started building tools to support the data analysis process using R. The first big project was Architect, which started as an eclipse-based R IDE, but more and more evolves into an IDE for data science more generally. In parallel we started working on infrastructure to automate R-based analyses and to plug R (and therefore statistical logic) into larger business processes and soon we had a tool suite to cover the needs of industry.

Ajay- What is RSB all about- what needs does it satisfy- who can use it ?

Tobias– RSB stands for the R Service Bus and is communication middleware and a work manager for R jobs. It allows to trigger and receive results from R jobs using a plethora of protocols such as RESTful web services, e-mail protocols, sftp, folder polling etc. The idea is to enable people to push a button (or software to make a request) and have them receive automated R based analysis results or reports for their data.

Ajay- What is your vision and what have been the challenges and learning so far in the project

Tobias– RSB started when automating toxicological analyses in pharmaceutical industry in collaboration with Philippe Lamote. Together with David Dossot, an exceptional software architect in Vancouver, we decided to cleanly separate concerns, namely to separate the integration layer (RSB) from the statistical layer (R) and, likewise, from the application layer. As a result any arbitrary R code can be run via RSB and any client application can interact with RSB as long as it can talk one of the many supported protocols. This fundamental design principle makes us different from alternative solutions where statistical logic and integration logic are always somehow interwoven, which results in maintenance and integration headaches. One of the challenges has been to keep focus on the core task of automating statistical analyses and not deviating into features that would turn RSB into a tool for interaction with an R session, which deserves an entirely different approach. Rservice-diagram

Ajay- Computing seems to be moving to an heterogeneous cloud , server and desktop model. What do you think about the R and Cloud Computing- current and future

Tobias– From a freedom perspective, cloud computing and the SaaS model is often a step backwards, but in our own practice we obviously follow our customers’ needs and offer RSB hosting from our data centers as well. Also, our other products e.g. the R IDE Architect are ready for the cloud and use on servers via Architect Server. As far as R itself concerns in relation to cloud computing, I foresee its use to increase. At Open Analytics we see an increasing demand for R-based statistical engines that power web applications living in the cloud.

Ajay- You recently released RSB version 6. What are all the new features. What is the planned roadmap going forward

Tobias– RSB 6.0 is all about large-scale production environments and strong security. It kicked off on a project where RSB was responsible for spitting 8500 predictions per second. Such large-scale production deployments of RSB motivated the development of a series of features. First of all RSB was made lightning fast: we achieved a full round trip from REST call to prediction in 7 ms on the mentioned use case. In order to allow for high throughput, RSB also gained a synchronous API (RSB 5.0 had an asynchronous API only). Another new feature is the availability of client-side connection pooling to the pool manager of R processes that are read to serve RSB. Besides speed, this type of production environments also need monitoring and resilience in case of issues. For the monitoring, we made sure that everything is in place for monitoring and remotely querying not only the RSB application itself, but also the pool of R processes managed by RServi.

 

(Note from Ajay- RJ is an open source library providing tools and interfaces to integrate R in Java applications. RJ project also provides a pool for R engines, easy to setup and manage by a web-interface or JMX. One or multiple client can borrow the R engines (called RServi)  see http://www.walware.de/it/rj/ and https://github.com/walware/rj-servi)
Also, we now allow to define node validation strategies to be able to check that R nodes are still functioning properly. If not, the nodes are killed and new nodes are started and added to the pool. In terms of security, we are now able to cover a very wide spectrum of authentication and authorization. We have machines up and running using openid, basic http authentication, LDAP, SSL client certificates etc. to serve everyone from the individual user who is happy with openid authentication for his RSB app to large investment banks who have very strong security requirements. The next step is to provide tighter integration with Architect, such that people can release new RSB applications without leaving the IDE.

Ajay- How does the startup ecosystem in Europe compare with say the SF Bay Area, What are some of the good things and not so great things

Tobias– I do not feel qualified to answer such a question, since I founded a single company in Antwerp, Belgium. That being said, Belgium is great! 🙂

Ajay- How can we popularize STEM education using MooCs , training etc

Tobias– Free software. Free as in beer and as in free speech!

Ajay- Describe the open source ecosystem in general and R ecosystem in  particular for Europe. How does it compare with other locations in your opinion

Tobias– Open source is probably a global ecosystem and crosses oceans very easily. Dries Buytaert started off Drupal in Belgium and now operates from the US interacting with a global community. From a business perspective, there are as many open source models as there are open source companies. I noticed that the major US R companies (Revolution Analytics and RStudio) cherished the open source philosophy initially, but drifted both into models combining open source and proprietary components. At Open Analytics, there are only open source products and enterprise customers have access to exactly the same functionality as a student may have in a developing country. That being said, I don’t believe this is a matter of geography, but has to do more with the origins and different strategies of the companies.

Ajay- What do you do for work life balance and de stressing when not shipping  code.

Tobias- In a previous life the athletics track helped keeping hands off the keyboard. Currently, my children find very effective ways to achieve similar goals

About-

OpenAnalytics is a consulting company specialized in statistical computing using open technologies. You can read more on it at http://www.openanalytics.eu

Using Windows Azure Machine Learning as a service with R #rstats

A Brief Tutorial I wrote by playing with the software at manage.windowsazure.com

Data Frame in Python

Exploring some Python Packages and R packages to move /work with both Python and R without melting your brain or exceeding your project deadline

—————————————

If you liked the data.frame structure in R, you have some way to work with them at a faster processing speed in Python.

Here are three packages that enable you to do so-

(1) pydataframe http://code.google.com/p/pydataframe/

An implemention of an almost R like DataFrame object. (install via Pypi/Pip: “pip install pydataframe”)

Usage:

        u = DataFrame( { "Field1": [1, 2, 3],
                        "Field2": ['abc', 'def', 'hgi']},
                        optional:
                         ['Field1', 'Field2']
                         ["rowOne", "rowTwo", "thirdRow"])

A DataFrame is basically a table with rows and columns.

Columns are named, rows are numbered (but can be named) and can be easily selected and calculated upon. Internally, columns are stored as 1d numpy arrays. If you set row names, they’re converted into a dictionary for fast access. There is a rich subselection/slicing API, see help(DataFrame.get_item) (it also works for setting values). Please note that any slice get’s you another DataFrame, to access individual entries use get_row(), get_column(), get_value().

DataFrames also understand basic arithmetic and you can either add (multiply,…) a constant value, or another DataFrame of the same size / with the same column names, like this:

#multiply every value in ColumnA that is smaller than 5 by 6.
my_df[my_df[:,'ColumnA'] < 5, 'ColumnA'] *= 6

#you always need to specify both row and column selectors, use : to mean everything
my_df[:, 'ColumnB'] = my_df[:,'ColumnA'] + my_df[:, 'ColumnC']

#let's take every row that starts with Shu in ColumnA and replace it with a new list (comprehension)
select = my_df.where(lambda row: row['ColumnA'].startswith('Shu'))
my_df[select, 'ColumnA'] = [row['ColumnA'].replace('Shu', 'Sha') for row in my_df[select,:].iter_rows()]

Dataframes talk directly to R via rpy2 (rpy2 is not a prerequiste for the library!)

 

(2) pandas http://pandas.pydata.org/

Library Highlights

  • A fast and efficient DataFrame object for data manipulation with integrated indexing;
  • Tools for reading and writing data between in-memory data structures and different formats: CSV and text files, Microsoft Excel, SQL databases, and the fast HDF5 format;
  • Intelligent data alignment and integrated handling of missing data: gain automatic label-based alignment in computations and easily manipulate messy data into an orderly form;
  • Flexible reshaping and pivoting of data sets;
  • Intelligent label-based slicing, fancy indexing, and subsetting of large data sets;
  • Columns can be inserted and deleted from data structures for size mutability;
  • Aggregating or transforming data with a powerful group by engine allowing split-apply-combine operations on data sets;
  • High performance merging and joining of data sets;
  • Hierarchical axis indexing provides an intuitive way of working with high-dimensional data in a lower-dimensional data structure;
  • Time series-functionality: date range generation and frequency conversion, moving window statistics, moving window linear regressions, date shifting and lagging. Even create domain-specific time offsets and join time series without losing data;
  • The library has been ruthlessly optimized for performance, with critical code paths compiled to C;
  • Python with pandas is in use in a wide variety of academic and commercial domains, including Finance, Neuroscience, Economics, Statistics, Advertising, Web Analytics, and more.

Why not R?

First of all, we love open source R! It is the most widely-used open source environment for statistical modeling and graphics, and it provided some early inspiration for pandas features. R users will be pleased to find this library adopts some of the best concepts of R, like the foundational DataFrame (one user familiar with R has described pandas as “R data.frame on steroids”). But pandas also seeks to solve some frustrations common to R users:

  • R has barebones data alignment and indexing functionality, leaving much work to the user. pandas makes it easy and intuitive to work with messy, irregularly indexed data, like time series data. pandas also provides rich tools, like hierarchical indexing, not found in R;
  • R is not well-suited to general purpose programming and system development. pandas enables you to do large-scale data processing seamlessly when developing your production applications;
  • Hybrid systems connecting R to a low-productivity systems language like Java, C++, or C# suffer from significantly reduced agility and maintainability, and you’re still stuck developing the system components in a low-productivity language;
  • The “copyleft” GPL license of R can create concerns for commercial software vendors who want to distribute R with their software under another license. Python and pandas use more permissive licenses.

(3) datamatrix http://pypi.python.org/pypi/datamatrix/0.8

datamatrix 0.8

A Pythonic implementation of R’s data.frame structure.

Latest Version: 0.9

This module allows access to comma- or other delimiter separated files as if they were tables, using a dictionary-like syntax. DataMatrix objects can be manipulated, rows and columns added and removed, or even transposed

—————————————————————–

Modeling in Python

Continue reading “Data Frame in Python”

RevoDeployR and commercial BI using R and R based cloud computing using Open CPU

Revolution Analytics has of course had RevoDeployR, and in a  webinar strive to bring it back to center spotlight.

BI is a good lucrative market, and visualization is a strength in R, so it is matter of time before we have more R based BI solutions. I really liked the two slides below for explaining RevoDeployR better to newbies like me (and many others!)

Integrating R into 3rd party and Web applications using RevoDeployR

Please click here to download the PDF.

Here are some additional links that may be of interest to you:

 

( I still think someone should make a commercial version of Jeroen Oom’s web interfaces and Jeff Horner’s web infrastructure (see below) for making customized Business Intelligence (BI) /Data Visualization solutions , UCLA and Vanderbilt are not exactly Stanford when it comes to deploying great academic solutions in the startup-tech world). I kind of think Google or someone at Revolution  should atleast dekko OpenCPU as a credible cloud solution in R.

I still cant figure out whether Revolution Analytics has a cloud computing strategy and Google seems to be working mysteriously as usual in broadening access to the Google Compute Cloud to the rest of R Community.

Open CPU  provides a free and open platform for statistical computing in the cloud. It is meant as an open, social analysis environment where people can share and run R functions and objects. For more details, visit the websit: www.opencpu.org

and esp see

https://public.opencpu.org/userapps/opencpu/opencpu.demo/runcode/

Jeff Horner’s

http://rapache.net/

Jerooen Oom’s

Talking on Big Data Analytics

I am going  being sponsored to a Government of India sponsored talk on Big Data Analytics at Bangalore on Friday the 13 th of July. If you are in Bangalore, India you may drop in for a dekko. Schedule and Abstracts (i am on page 7 out 9) .

Your tax payer money is hard at work- (hassi majak only if you are a desi. hassi to fassi.)

13 July 2012 (9.30 – 11.00 & 11.30 – 1.00)
Big Data Big Analytics
The talk will showcase using open source technologies in statistical computing for big data, namely the R programming language and its use cases in big data analysis. It will review case studies using the Amazon Cloud, custom packages in R for Big Data, tools like Revolution Analytics RevoScaleR package, as well as the newly launched SAP Hana used with R. We will also review Oracle R Enterprise. In addition we will show some case studies using BigML.com (using Clojure) , and approaches using PiCloud. In addition it will showcase some of Google APIs for Big Data Analysis.

Lastly we will talk on social media analysis ,national security use cases (i.e. cyber war) and privacy hazards of big data analytics.

Schedule

View more presentations from Ajay Ohri.
Abstracts

View more documents from Ajay Ohri.

 

Using Google Analytics with R

Some code to read in data from Google Analytics data. Some modifications include adding the SSL authentication code and modifying (in bold) the table.id parameter to choose correct website from a GA profile with many websites

The Google Analytics Package files can be downloaded from http://code.google.com/p/r-google-analytics/downloads/list

It provides access to Google Analytics data natively from the R Statistical Computing programming language. You can use this library to retrieve an R data.frame with Google Analytics data. Then perform advanced statistical analysis, like time series analysis and regressions.

Supported Features

  • Access to v2 of the Google Analytics Data Export API Data Feed
  • A QueryBuilder class to simplify creating API queries
  • API response is converted directly into R as a data.frame
  • Library returns the aggregates, and confidence intervals of the metrics, dynamically if they exist
  • Auto-pagination to return more than 10,000 rows of information by combining multiple data requests. (Upper Limit 1M rows)
  • Authorization through the ClientLogin routine
  • Access to all the profiles ids for the authorized user
  • Full documentation and unit tests
Code-

> library(XML)

>

> library(RCurl)

Loading required package: bitops

>

> #Change path name in the following to the folder you downloaded the Google Analytics Package

>

> source(“C:/Users/KUs/Desktop/CANADA/R/RGoogleAnalytics/R/RGoogleAnalytics.R”)

>

> source(“C:/Users/KUs/Desktop/CANADA/R/RGoogleAnalytics/R/QueryBuilder.R”)

> # download the file needed for authentication

> download.file(url=”http://curl.haxx.se/ca/cacert.pem&#8221;, destfile=”cacert.pem”)

trying URL ‘http://curl.haxx.se/ca/cacert.pem&#8217; Content type ‘text/plain’ length 215993 bytes (210 Kb) opened

URL downloaded 210 Kb

>

> # set the curl options

> curl <- getCurlHandle()

> options(RCurlOptions = list(capath = system.file(“CurlSSL”, “cacert.pem”,

+ package = “RCurl”),

+ ssl.verifypeer = FALSE))

> curlSetOpt(.opts = list(proxy = ‘proxyserver:port’), curl = curl)

An object of class “CURLHandle” Slot “ref”: <pointer: 0000000006AA2B70>

>

> # 1. Create a new Google Analytics API object

>

> ga <- RGoogleAnalytics()

>

> # 2. Authorize the object with your Google Analytics Account Credentials

>

> ga$SetCredentials(“USERNAME”, “PASSWORD”)

>

> # 3. Get the list of different profiles, to help build the query

>

> profiles <- ga$GetProfileData()

>

> profiles #Error Check to See if we get the right website

$profile AccountName ProfileName TableId

1 dudeofdata.com dudeofdata.com ga:44926237

2 knol.google.com knol.google.com ga:45564890

3 decisionstats.com decisionstats.com ga:46751946

$total.results

total.results

1 3

>

> # 4. Build the Data Export API query

>

> #Modify the start.date and end.date parameters based on data requirements

>

> #Modify the table.id at table.id = paste(profiles$profile[X,3]) to get the X th website in your profile

> # 4. Build the Data Export API query

> query <- QueryBuilder() > query$Init(start.date = “2012-01-09”, + end.date = “2012-03-20”, + dimensions = “ga:date”,

+ metrics = “ga:visitors”,

+ sort = “ga:date”,

+ table.id = paste(profiles$profile[3,3]))

>

>

> #5. Make a request to get the data from the API

>

> ga.data <- ga$GetReportData(query)

[1] “Executing query: https://www.google.com/analytics/feeds/data?start-date=2012%2D01%2D09&end-date=2012%2D03%2D20&dimensions=ga%3Adate&metrics=ga%3Avisitors&sort=ga%3Adate&ids=ga%3A46751946&#8221;

>

> #6. Look at the returned data

>

> str(ga.data)

List of 3

$ data :’data.frame’: 72 obs. of 2 variables: ..

$ ga:date : chr [1:72] “20120109” “20120110” “20120111” “20120112” … ..

$ ga:visitors: num [1:72] 394 405 381 390 323 47 169 67 94 89 …

$ aggr.totals :’data.frame’: 1 obs. of 1 variable: ..

$ aggregate.totals: num 28348

$ total.results: num 72

>

> head(ga.data$data)

ga:date ga:visitors

1 20120109 394

2 20120110 405

3 20120111 381

4 20120112 390

5 20120113 323

6 20120114 47 >

> #Plotting the Traffic >

> plot(ga.data$data[,2],type=”l”)

Update- Some errors come from pasting Latex directly to WordPress. Here is some code , made pretty-r in case you want to play with the GA api

library(XML)

library(RCurl)

#Change path name in the following to the folder you downloaded the Google Analytics Package 

source("C:/Users/KUs/Desktop/CANADA/R/RGoogleAnalytics/R/RGoogleAnalytics.R")

source("C:/Users/KUs/Desktop/CANADA/R/RGoogleAnalytics/R/QueryBuilder.R")
# download the file needed for authentication
download.file(url="http://curl.haxx.se/ca/cacert.pem", destfile="cacert.pem")

# set the curl options
curl <- getCurlHandle()
options(RCurlOptions = list(capath = system.file("CurlSSL", "cacert.pem",
package = "RCurl"),
ssl.verifypeer = FALSE))
curlSetOpt(.opts = list(proxy = 'proxyserver:port'), curl = curl)

# 1. Create a new Google Analytics API object 

ga <- RGoogleAnalytics()

# 2. Authorize the object with your Google Analytics Account Credentials 

ga$SetCredentials("ohri2007@gmail.com", "XXXXXXX")

# 3. Get the list of different profiles, to help build the query

profiles <- ga$GetProfileData()

profiles #Error Check to See if we get the right website

# 4. Build the Data Export API query 

#Modify the start.date and end.date parameters based on data requirements 

#Modify the table.id at table.id = paste(profiles$profile[X,3]) to get the X th website in your profile 
# 4. Build the Data Export API query
query <- QueryBuilder()
query$Init(start.date = "2012-01-09",
                   end.date = "2012-03-20",
                   dimensions = "ga:date",
                   metrics = "ga:visitors",
                   sort = "ga:date",
                   table.id = paste(profiles$profile[3,3]))

#5. Make a request to get the data from the API 

ga.data <- ga$GetReportData(query)

#6. Look at the returned data 

str(ga.data)

head(ga.data$data)

#Plotting the Traffic 

plot(ga.data$data[,2],type="l")

Created by Pretty R at inside-R.org

Teradata updates Teradata-R

The Teradata add-on package for R

teradataR is a package or library that allows R users to easily connect to Teradata, establish data frames (R data formats) to Teradata and to call in-database analytic functions within Teradata.  This allows R users to work within their R console environment while leveraging the in-database functions developed with Teradata Warehouse Miner. This package provides 44 different analytical functions and an additional 20 data connection and R infrastructure functions.  In addition, we’ve added a function that will list the stored procedures within Teradata provide the capability to call functions from R.

  • 20 Functions to enable R infrastructure to operate with Teradata
  • tdConnect – Connect to Teradata via ODBC
  • Td.data.frame – Establish data frame connections to a Teradata table
  • 44 in-database analytical functions callable from R.  Sample of the functions include:
  • Descriptive statistics: Overlap, histogram, frequency, statistics, matrix functions, and values analysis
  • Reorganization functions: join, merge and samples
  • Transformations: bincode, recode, rescale, sigmoid, zscore and null replacement
  • K-Means clustering and Score K-Means
  • Statistical tests: ks, dagostino.pearson, shapiro.wilk, bionomial, and wilcoxon
  • R language features nrow, ncol, min, max, summary, as.dataframe, and dim
  • Tool and R functions that allow users to create their own custom analytic functions that’s callable by R.
  • Teradata Warehouse Miner can capture any analytic stream including UDFs and create a stored procedure
    • Analytic process to create new derived predictive variables can be captured as a stored procedure.
    • Entire process to create or update an analytical data set can be captured as a stored procedure.
    • R function can list all the stored procedures within Teradata.
    • R function can call a stored procedure that runs in-database

TeradataR allows R users to leverage all the benefits of in-database processing with Teradata:

  • Eliminate data movement from Teradata to the R framework for key data intensive tasks.
  • Leverage the speed of Teradata database’s parallel processing to run analytics against big data.
  • Ability to operate within the R console environment.
  • Embed your frequently performed tasks to run in-database.
  • R and TeradataR are free downloads.

Source- http://developer.teradata.com/applications/articles/in-database-analytics-with-teradata-r

This package allows users of R to interact with a Teradata database. R is an open source language for statistical computing and graphics. R provides a wide variety of statistical (linear and nonlinear modeling, classical statistical tests, time-series analysis, classification, clustering) and graphical techniques, and is highly extensible. Users can use many statistical functions directly against the Teradata system without having to extract the data into memory.

Enhancements included with this new 1.0.1 release include:

  • teradataR User Guide
  • addition of Mac OS X Package
  • addition of Red Hat Linux Package (added 2/23/12)
  • summary has been enhanced to run faster
  • JDBC support added to allow Windows or Mac users to run the package with JDBC
  • td.data.frame enhanced to allow support for manipulation to add columns and expressions
  • td.data.frame enhanced to use Teradata 14.0 Fastpath Transform Functions (see Appendix B)
  • td.tapply function added to apply a select group of functions to columns of an array

From-http://downloads.teradata.com/download/applications/teradata-r

and

A new R package for Red Hat Linux has been added to the teradataR 1.0.1 release. This new package provides the same functionality as in the previously released Windows and Mac OS X packages, but is built for Red Hat Linux. This version was built and tested on Red Hat Linux 6.2 32-bit. (The R version for Red Hat Linux is 2.14.1)

Installing this package is the same as any normal R package; just extract it into your R library area, or use the install.packagescommand with the file path.

from- http://developer.teradata.com/tag/r

and

With plenty of prolific and enthusiastic developers, the number of packages for R is expected to grow tremendously. Statisticians and analysts using these packages will find innovative ways to use data to answer their research and business questions. And as organizations become more willing to rely on open-source software for mission-critical tasks, R is poised to become an essential tool for analyzing our complex world.

Source-http://www.teradatamagazine.com/v09n03/Connections/R-you-ready/

From the user guide-

http://downloads.teradata.com/download/applications/teradata-r

teradataR allows R users to easily connect to Teradata, establish td data frames (virtual R data frames) to
Teradata and to call in-database analytic functions within Teradata. This allows R users to work within their R
console environment while leveraging the in-database functions

A Function List
teradataR-package  Allow access to Teradata via R
as.data.frame.td.data.frame Convert td data frame to a data frame
as.td.data.frame Coerce to a td data frame
dim.td.data.frame Dimensions of a td data frame
hist.td.data.frame Histograms
Is.td.data.frame Is an Object a Teradata Data Frame
Is.td.expression Is an Object a Teradata Expression
mean.td.data.frame Arithmetic Mean
median.td.data.frame Median Value
min.td.data.frame Minima
predict.kmeans Kmeans Model Prediction
print.td.data.frame Show contents of a td data frame
sum.td.data.frame Sum of column
summary.td.data.frame Summary of Teradata Data Frame
Td.bincode Create Table of Bincode Values
Td.binomial Binomial Test
Td.binomialsign Binomial Sign Test
Td.call.sp Locate and call stored procedure
Td.cor Correlation Matrix
Td.cov Covariance Matrix
Td.dagostino.pearson D’Agostino Pearson Test
Td.data.frame Teradata Data Frames
Td.f.oneway One way F Test
Td.factanal Factor Analysis
Td.freq Frequency Analysis
Td.hist Histograms
Td.join Join Tables in Teradata
Td.kmeans K-Means Clustering
Td.ks Kolmogorov Smirnov Test
Td.lilliefors Lilliefors Test
Td.merge Merge Rows of Teradata Tables
Td.mode Mode Value of Column
Td.mwnkw Mann-Whitney/Kruskal Wallis Test
Td.nullreplace Replace Null Values
Td.overlap Overlap
Td.quantiles Quantile Values
Td.rank Rank
Td.recode Recode
Td.rescale Rescale Values of Column
Td.sample Sample Rows
Td.shapiro.wilk Shapiro Wilk
Td.sigmoid Sigmoid Transformation
Td.smirnov Smirnov Test
Td.solve Solve a system of equations
Td.stats General Statistics
Td.t.paired T Test Paired
Td.t.unpaired T Test Unpaired
Td.t.unpairedi T Test – Unpaired Indicator
Td.values Values
Td.wilcoxon Wilcoxon Test
Td.zscore Zscore Transformation
tdClose Close connection
tdConnect Connect to Teradata database
tdMetadataDB Set metadata database
tdQuery Query Teradata Database
teradataR Allow access to Teradata via R
[.td.data.frame Extract Teradata Data Frame
[<-.td.data.frame Replace value of Teradata Data Frame