accumulator

问题 I have a .txt file that I created with multiple lines. when I run a for loop, with a count accumulator, it skips lines. It skips the top line, and starts with the second, prints the fourth, the sixth, etc... What is it I'm missing? ** for your reading pleasure** def main(): # Open file line_numbers.txt data_file = open('line_numbers.txt', 'r') # initialize accumulatior count = 1 # Read all lines in data_file for line in data_file: # Get the data from the file line = data_file.readline() #

问题 I'm looking for a fast solution to MATLAB's accumarray in numpy. The accumarray accumulates the elements of an array which belong to the same index. An example: a = np.arange(1,11) # array([ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]) accmap = np.array([0,1,0,0,0,1,1,2,2,1]) Result should be array([13, 25, 17]) What I've done so far: I've tried the accum function in the recipe here which works fine but is slow. accmap = np.repeat(np.arange(1000), 20) a = np.random.randn(accmap.size) %timeit accum(accmap,

问题 In Java 8, Stream has a method reduce: T reduce(T identity, BinaryOperator<T> accumulator); Is the accumulator operator allowed to modify either of its arguments? I presume not since the JavaDoc says the accumulator should be NonInterfering, though all examples talk of modifying the collection, rather than modifying the elements of the collection. So, for a concrete example, if we have integers.reduce(0, Integer::sum); and suppose for a moment that Integer was mutable, would sum be allowed to

问题 I have a MATLAB function block in simulink and for each step simlulink does I want to input a counter with increment 1. Ex: 1st Step -> Acc=1 2nd Step -> Acc=2 I tried using a Count up block + Pulse generator but the time step of simulink is not constant. Any ideas? 回答1: A common way to do this is to use a sum and a memory block with an initial condition of 0. It should count steps in both fixed and variable step simulations. In fact I believe this would be build and perform very much like an

问题 Is there any way to set the accumulator to 0 after every time we use it and after that it still performs the same function? or How to calculate the overall value for each key in a Map like this : String, Hashmap String, Integer ? I am trying to be as clarifying as I can but I don't have a clue about that. /*EXAMPLE OF HASHMAP: String e.g - UK ; America ; Africa , etc. String e.g - black , white, asian Integer e.g- 2008 , 103432 , 2391 // for every country the values are diff */ //one way to

问题 I have been thinking of how to perform this operation on CUDA using reductions, but I'm a bit at a loss as to how to accomplish it. The C code is below. The important part to keep in mind -- the variable precalculatedValue depends on both loop iterators. Also, the variable ngo is not unique to every value of m ... e.g. m = 0,1,2 might have ngo = 1, whereas m = 4,5,6,7,8 could have ngo = 2, etc. I have included sizes of loop iterators in case it helps to provide better implementation

问题 I am running this simple code: val accum = sc.accumulator(0, "Progress"); listFilesPar.foreach { filepath => accum += 1 } listFilesPar is an RDD[String] which throws the following error: org.apache.spark.SparkException: Task not serializable Right now I don't understand what's happening and I don't put parenthesis but brackets because I need to write a lengthy function. I am just doing unit testing 回答1: The typical cause of this is that the closure unexpectedly captures something. Something

问题 I want to create an accumulator for lists of type List[(String, String)]. I first created the following object: object ListAccumulator extends AccumulatorParam[List[(String, String)]] { def zero(initialValue: List[(String, String)]): List[(String, String)] = { Nil } def addInPlace(list1: List[(String, String)], list2: List[(String, String)]): List[(String, String)] = { list1 ::: list2 } } In the same file (SparkQueries.scala) I tried to use it within a function in my class: val resultList =

问题 I must write a function that computes and returns the cosine of an angle using the first 10 terms of the following series: cosx = 1 - (x**2)/2! + (x**4)/4! - (x**6)/6!.... I can't use the factorial function, but i can use the fact that if the previous denominator was n! , the current denominator would be n!(n+1)(n+2) . I'm trying to use an accumulator loop, but i'm having a hard time with the fact that it alternates from positive to negative and also having trouble with the denominator. This

问题 I'm thinking of purchasing Opticon PHL 7112 accumulator which runs on Windows CE 5.0 i was wondering will i be able to: develop an application that connects to an open MSSQL database is there a capability to get data from a SOAP web service? i saw that only visual studio 2008 support development for windows ce, is there a way to enable this on visual studio 2010-2012 ? if possible to connect to MSSQL database how to do it if only possible to connect to a SOAP web services how to do it I'm new