coursera spark

function and map the given set to another set. The signature is as follows: def map(s: Set, f: Int => Int): Set The second parameter f is used to map the elements of the original set to the functions of the new set (first-class citizen !) The question looks simple, just to judge whether the elements in s are equal to the input integer after f ing. This includes two steps: 1. Is there any element in s that meets a specific condition (assertion )? 2. The specific condition (assertion) is mapped t

, i.e., all of our training examples lie perfectly on some straigh T line. If J (θ0,θ1) =0, that means the line defined by the equation "y=θ0+θ1x" perfectly fits all of our data. For the To is true, we must has Y (i) =0 for every value of i=1,2,..., m. So long as any of our training examples lie on a straight line, we'll be able to findθ0 andθ1 so, J (θ0,θ1) =0. It is not a necessary that Y (i) =0 for all of our examples. We can perfectly predict the value o

-Learning RateIn the gradient descent algorithm, the number of iterations required for the algorithm convergence varies according to the model. Since we cannot predict in advance, we can plot the corresponding graphs of iteration times and cost functions to observe when the algorithm tends to converge.Of course, there are some ways to automatically detect convergence, for example, we compare the change value of a cost function with a predetermined threshold, such as 0.001, to determine convergen

-Gradient descent for linear regressionHere we apply the gradient descent algorithm to the linear regression model, we first review the gradient descent algorithm and the linear regression model:We then expand the slope of the gradient descent algorithm to the partial derivative:In most cases, the linear regression model cost function is shaped like a convex body, so the local minimum value is equivalent to the global minimum:The following is the entire convergence and parameter determination pr

-Gradient descentThe gradient descent algorithm is an algorithm for calculating the minimum value of a function, and here we will use the gradient descent algorithm to find the minimum value of the cost function.The idea of a gradient descent is that we randomly select a combination of parameters and calculate the cost function at the beginning, and then we look for the next combination of parameters that will reduce the value of the cost function.We continue this process until a local minimum (

(x.next[c], key, d+1); the returnx; * } $ Panax Notoginseng Public Booleancontains (String key) - { theNode x = Get (root, key, 0); + if(x = =NULL)return false; A returnX.hasword; the } + - PrivateNode get (node X, String key,intd) $ { $ if(x = =NULL)return NULL; - if(d = = Key.length ())returnx; - intc =charAt (key, D); the returnGet (X.next[c], key, d+1); - }Wuyi the Public BooleanHaskeyswi

use of MATLAB. *.4.gradientdescent.mfunction [Theta, j_history] =gradientdescent (X, y, theta, Alpha, num_iters)%gradientdescent performs gradient descent to learn theta% theta = gradientdescent (X, y, theta, Alpha, num_iters) up Dates theta by% taking num_iters gradient steps with learning rate alpha% Initialize Some useful valuesm= Length (y);%Number of training examplesj_history= Zeros (Num_iters,1); forITER =1: Num_iters% ====================== YOUR CODE here ======================% instru

Overview photo OCR problem Description and Pipeline sliding Windows getting Lots of data and Artificial data ceiling analysis:what part of the Pipeline to work on Next Review Lecture Slides Quiz:Application:Photo OCR Conclusion Summary and Thank You Log 4/20/2017:1.1, 1.2; Note Ocr? ... Coursera-machine Learning, Stanford:w

I've been procrastinating for the last time, and I'm going to keep it up today. Programming Title #: Calculating the sum of the edge elements of a matrix Source: POJ (Coursera statement: The exercises completed on POJ will not be counted into Coursera's final results. ) Note: Total time limit: 1000ms memory limit: 65536kB description Enter an integer matrix to compute the sum of elements at the edge of the matrix. The elements of the so-called matrix

Week 3 Quizhelp Center Warning:the hard deadline has passed. You can attempt it, but and you won't be. You are are welcome to try it as a learning exercise. In accordance with the Coursera Honor Code, I certify this answers here are I own work. Question 1 Assume you are using a Unigram language model to calculate the probabilities of phrases. Then, the probabilities of generating the phrases "study text mining" and "text mining study" are not equal, i

Week 3 Practice quizhelp Center Warning:the hard deadline has passed. You can attempt it, but and you won't be. You are are welcome to try it as a learning exercise. In accordance with the Coursera Honor Code, I certify this answers here are I own work. Question 1 are given a vocabulary composed of only three words: "text", "mining", and "the". Below are the probabilities of two of this three words given by a Unigram model: Word Probability Text 0.4 M

Zhou Zhihu L.Holiday, finally can spare time to update the blog ....1. Get DataThis article provides a detailed introduction to Sparksql's content by using the Spark project git log on GitHub as the data.The Data Acquisition command is as follows:[[emailprotected] spark]# git log --pretty=format:‘{"commit":"%H","author":"%an","author_email":"%ae","date":"%ad","message":"%f"}‘ > sparktest.jsonThe output of

Tags: spark books spark hotspot Spark Technology spark tutorial The command to end historyserver is as follows: Step 4: Verify the hadoop distributed Cluster First, create two directories on the HDFS file system. The creation process is as follows: /Data/wordcount in HDFS is used to store the data f

Open idea under the SRC under main under Scala right click to create a Scala class named Simpleapp, the content is as followsOrg.apache.spark.SparkContext org.apache.spark.sparkcontext._ org.apache.spark.SparkConf"a"). Count () numbs = logdata.filter (line = Line.contains ("B")). Count () println ("Lines with a:%s, Lines with B:%s". Format (Numas, numbs))}} Packaging files:File-->>projectstructure-click artificats-->> click the Green Plus-click jar-->> Select from module with Depe

Step 2: Use the spark cache mechanism to observe the Efficiency Improvement Based on the above content, we are executing the following statement: 650) This. width = 650; "src =" http://s3.51cto.com/wyfs02/M00/49/AF/wKioL1QY8tmiGO95AAG6MKKe5vI885.jpg "style =" float: none; "Title =" 1.png" alt = "wkiol1qy8tmigo95aag6mkke5vi885.jpg"/> 650) This. width = 650; "src =" http://s3.51cto.com/wyfs02/M00/49/AD/wKiom1QY8sLjnB_KAAHXbDhuD_I646.jpg "style =" float

Next package, use Project structure's artifacts:Using the From modules with dependencies:Select Main Class:Click "OK":Change the name to Sparkdemojar:Because Scala and spark are installed on each machine, you can delete both Scala and spark-related jar files:Next Build:Select "Build Artifacts":The rest of the operation is to upload the jar package to the server, and then execute the

Next package, use Project structure's artifacts:Using the From modules with dependencies:Select Main Class:Click "OK":Change the name to Sparkdemojar:Because Scala and spark are installed on each machine, you can delete both Scala and spark-related jar files:Next Build:Select "Build Artifacts":The rest of the operation is to upload the jar package to the server, and then execute the

Create a Scala idea project:Click "Next":Click "Finish" to complete the project creation:To modify an item's properties:First modify the Modules option:Create two folders under SRC and change their properties to source:Then modify the libraries:Because you want to develop the spark program, you need to bring in the jar packages that spark needs to develop:After the import package is complete, create a packa

Create a Scala idea project:Click "Next":Click "Finish" to complete the project creation:To modify an item's properties:First modify the Modules option:Create two folders under SRC and change their properties to source:Then modify the libraries:Because you want to develop the spark program, you need to bring in the jar packages that spark needs to develop:After the import package is complete, create a packa

Step 2: Use the spark cache mechanism to observe the Efficiency Improvement Based on the above content, we are executing the following statement: It is found that the same calculation result is 15. In this case, go to the Web console: The console clearly shows that we performed the "count" Operation twice. Now we will execute the "Sparks" variable for the "cache" Operation: Run the Count operation to view the Web console: At this tim