iteration

The fastest way to iterate through a collection of objects

Hello all, First to give you some background: I have some research code which performs a Monte Carlo simulation, essential what happens is I iterate through a collection of objects, compute a number of vectors from their surface then for each vector I iterate through the collection of objects again to see if the vector hits another obje...

Iterating over two dimension array and knowing current position

I am trying to iterate a multidimension array created with the following line To iterate i'm using the following code visiblematrix= Array.new (10) {Array.new(10){0}} But this doesn't allow me to know the current x,y position while iterating. how can i find it out without resorting to temporary variables visiblematrix.each do |x| ...

compare two following values in numpy array

What is the best way to touch two following values in an numpy array? example: npdata = np.array([13,15,20,25]) for i in range( len(npdata) ): print npdata[i] - npdata[i+1] this looks really messed up and additionally needs exception code for the last iteration of the loop. any ideas? Thanks! ...

BASH statements execute alone but return "no such file" in for loop.

Another one I can't find an answer for, and it feels like I've gone mad. I have a BASH script using a for loop to run a complex command (many protein sequence alignments) on a lot of files (~5000). The loop produces statements that will execute when given alone (i.e. copy-pasted from the error message to the command prompt), but which r...

Optimal way to generate list of PHP object properties with delimiter character, implode()?

I am trying to find out if there is a more optimal way for creating a list of an object's sub object's properties. (Apologies for the crude wording, I am not really much of an OO expert) I have an object "event" that has a collection of "artists", each artist having an "artist_name". On my HTML output, I want a plain list of artist name...

Handling large (object) datasets with PHP

I am currently working on a project that extensively relies on the EAV model. Both entities as their attributes are individually represented by a model, sometimes extending other models (or at least, base models). This has worked quite well so far since most areas of the application only rely on filtered sets of entities, and not the en...

array iteration strstr in c

I was wondering if it's safe to do the following iteration to find the first occurrence of str within the array or if there is a better way. Thanks #include <stdio.h> #include <string.h> const char * list[] = {"One","Two","Three","Four","Five"}; char *c(char * str) { int i; for (i = 0; i < 5; i++) { if (strstr(str, li...

iteration in latex

Hi, I would like to use some iteration control flow to simplify the following latex code \begin{sidewaystable} \caption{A glance of images} \centering \begin{tabular}{| c ||c| c| c |c| c|| c |c| c|c|c| } \hline \backslashbox{Theme}{Class} &\multicolumn{5}{|c|}{Class 0} & \multicolumn{5}{|c|}{Class 1} \\ ...

Recursion and Iteration

What is the difference? Are these the same? If not, can someone please give me an example? MW: Iteration - 1 : the action or a process of iterating or repeating: as a : a procedure in which repetition of a sequence of operations yields results successively closer to a desired result b : the repetition of a sequence of computer instruct...

(C#) iterate over read-only private collection member

I have a class which has two HashSet<String> collections as private members. Other classes in my code would like to be able to iterate over those HashSets and read their contents. I don't want to write a standard getter because another class could still do something like myClass.getHashSet().Clear(); Is there any other way to expose t...

How do I iterate over the properties of an anonymous object in C#?

I want to take an anonymous object as argument to a method, and then iterate over its properties to add each property/value to a a dynamic ExpandoObject. So what I need is to go from new { Prop1 = "first value", Prop2 = SomeObjectInstance, Prop3 = 1234 } to knowing names and values of each property, and being able to add them to t...

Bash: Correct way to Iterate over Map

In Bash I can create a map (hashtable) with this common construction hput() { eval "$1""$2"='$3' } hget() { eval echo '${'"$1$2"'#hash}' } and then use it like this: hput capitals France Paris hput capitals Spain Madrid echo "$(hget capitols France)" But how do I best iterate over the entries in the map ?. For instance, in J...

More advanced usage of interfaces

To be honest I'm not quite sure if I understand the task myself :) I was told to create class MySimpleIt, that implements Iterator and Iterable and will allow to run the provided test code. Arguments and variables of objects cannot be either Collections or arrays. The code : MySimpleIt msi=new MySimple(10,100, ...

How can I iterate over a recordset within a stored procedure?

I need to iterate over a recordset from a stored procedure and execute another stored procedure using each fields as arguments. I can't complete this iteration in the code. I have found samples on the internets, but they all seem to deal with a counter. I'm not sure if my problem involved a counter. I need the T-SQL equivalent of a forea...

Report structure

I'm in the documentation phase and have used an iteration-based model for my project. The model focus is to divide up the report after releases, which means I must have an analysis, design and construction under each releases in the report. The result of the report would probably be very complex and unstructured. Then I would for instanc...

Python: Remove items from a list while iterating in Python

Possible Duplicate: Remove items from a list while iterating in Python My problem is simple: I have a long list of elements that I want to iterate through and check every element against a condition. Depending on the outcome of the condition I would like to delete the current element of the list, and continue iterating over it...

Python: Memory usage and optimization when modifying lists

The problem My concern is the following: I am storing a relativity large dataset in a classical python list and in order to process the data I must iterate over the list several times, perform some operations on the elements, and often pop an item out of the list. It seems that deleting one item out of a Python list costs O(N) since Py...

std::list or std::multimap

Hey, I right now have a list of a struct that I made, I sort this list everytime I add a new object, using the std::list sort method. I want to know what would be faster, using a std::multimap for this or std::list, since I'm iterating the whole list every frame (I am making a game). I would like to hear your opinion, for what should I ...

Recursive vs. Iterative algorithms

I'm implementing the Euclidian algorithm for finding the GCD (Greatest Common Divisor) of two integers. Two sample implementations are given: Recursive and Iterative. http://en.wikipedia.org/wiki/Euclidean_algorithm#Implementations My Question: In school I remember my professors talking about recursive functions like they were all th...

Python list comprehension to return edge values of a list

If I have a list in python such as: stuff = [1, 2, 3, 4, 5, 6, 7, 8, 9] with length n (in this case 9) and I am interested in creating lists of length n/2 (in this case 4). I want all possible sets of n/2 values in the original list, for example: [1, 2, 3, 4], [2, 3, 4, 5], ..., [9, 1, 2, 3] is there some list comprehension c...