map-function

I am trying to combine the solutions provided in both of these SO answers - Using threading to slice an array into chunks and perform calculation on each chunk and reassemble the returned arrays into one array and Pass multiple parameters to concurrent.futures.Executor.map? . I have a numpy array that I chunk into segments and I want each chunk to be sent to a separate thread and an additional argument to be sent along with the chunk of the original array. This additional argument is a constant and will not change. The performCalc is a function that will take two arguments -one the chunk of

I apologize for the unclear topic title. I have this function in Scheme which is a custom implementation of the map function. It works fine, but I got lost trying to understand it. (define (my-map proc . ls) (letrec ((iter (lambda (proc ls0) (if (null? ls0) '() (cons (proc (car ls0)) (iter proc (cdr ls0)))))) (map-rec (lambda (proc ls0) (if (memq '() ls0) '() (cons (apply proc (iter car ls0)) (map-rec proc (iter cdr ls0))))))) (map-rec proc ls))) The problem lays in cons (proc (car ls0)) . If I'm correct, when passing (1 2 3) (4 5 6) to the ls parameter the actual value of it will be ((1 2 3)

I nee to use the conditional statement in a map function I am duplicating each single value of a path d in a SVG but i do not want this happening for the objects M and L of the array Here is an example of the array as string. M 175 0 L 326.55444566227675 87.50000000000001 L 326.55444566227675 262.5 L 175 350 L 23.445554337723223 262.5 L 23.44555433772325 87.49999999999999 L 175 0 This is an example to my case without the conditional statement let neWd = array.map(x => { return x * 2; }).reverse().join(' ') how can i write down this in e6 ? I don not want the multiplication happening for the

The following code: let resultsArray = Array.apply(null, Array(10)).map(Number.prototype.valueOf,0); creates the following array [0, 0, 0, 0, 0, 0, 0, 0, 0, 0] Why does map() need Number.prototype.valueOf just to push the number 0 in to each position of this array. Is there a different (more efficient) way to achieve this result, or is this the best way? Techniv If you read the map documentation you can read this: The map() method creates a new array with the results of calling a provided function on every element in this array. So you need to use the function Number.prototype.valueOf in first

This question already has an answer here: Python 3 vs Python 2 map behavior 3 answers I am doing the following in Python2.7: >>> a = [1,2,3,4,5] >>> b = [2,1,3,4] >>> c = [3,4] >>> map(None, a, b, c) [(1, 2, 3), (2, 1, 4), (3, 3, None), (4, 4, None), (5, None, None)] I am trying to do something similar in Python3 >>> a = [1,2,3,4,5] >>> b = [2,1,3,4] >>> c = [3,4] >>> map(None, a, b, c) <map object at 0xb72289ec> >>> for i,j,k in map(None, a, b, c): ... print (i,j,k) ... Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: 'NoneType' object is not callable How do I

In Spark SQL when I tried to use map function on DataFrame then I am getting below error. The method map(Function1, ClassTag) in the type DataFrame is not applicable for the arguments (new Function(){}) I am following spark 1.3 documentation as well. https://spark.apache.org/docs/latest/sql-programming-guide.html#inferring-the-schema-using-reflection Have any one solution? Here is my testing code. // SQL can be run over RDDs that have been registered as tables. DataFrame teenagers = sqlContext.sql("SELECT name FROM people WHERE age >= 13 AND age <= 19"); List<String> teenagerNames = teenagers

This question already has an answer here: How do I stop iteration and return an error when Iterator::map returns a Result::Err? 2 answers I have code like this: let things = vec![/* ...*/]; // e.g. Vec<String> things .map(|thing| { let a = try!(do_stuff(thing)); Ok(other_stuff(a)) }) .filter(|thing_result| match *thing_result { Err(e) => true, Ok(a) => check(a), }) .map(|thing_result| { let a = try!(thing_result); // do stuff b }) .collect::<Result<Vec<_>, _>>() In terms of semantics, I want to stop processing after the first error. The above code works, but it feels quite cumbersome. Is there

How can I make multiprocessing.pool.map distribute processes in numerical order? More Info: I have a program which processes a few thousand data files, making a plot of each one. I'm using a multiprocessing.pool.map to distribute each file to a processor and it works great. Sometimes this takes a long time, and it would be nice to look at the output images as the program is running. This would be a lot easier if the map process distributed the snapshots in order; instead, for the particular run I just executed, the first 8 snapshots analyzed were: 0, 78, 156, 234, 312, 390, 468, 546 . Is there