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  • Avoid the use of loops (for) with R

    - by albergali
    Hi, I'm working with R and I have a code like this: i<-1 j<-1 for (i in 1:10) for (j in 1:100) if (data[i] == paths[j,1]) cluster[i,4] <- paths[j,2] where : data is a vector with 100 rows and 1 column paths is a matrix with 100 rows and 5 columns cluster is a matrix with 100 rows and 5 columns My question is: how could I avoid the use of "for" loops to iterate through the matrix? I don't know whether apply functions (lapply, tapply...) are useful in this case. This is a problem when j=10000 for example, because execution time is very long. Thank you

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  • How to create reusable WPF grid layout

    - by zendar
    I have a window with tab control and number of pages - tab items. Each tab item has same grid layout - 6 rows and 4 columns. Now, each tab item contains grid with row and column definitions, so almost half of XAML is definition of grids. How can I define this grid in one place and reuse that definition in my application? Template? User control? Besides 6x4, I have only two more grid dimensions that repeat: 8x4 and 6x6.

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  • How to redirect to the current page with form in php?

    - by garcon1986
    Hello, I tried to redirect to the current page with form in my php application. Now i have met a problem. <form name="myform" action="?page=matching" method="GET"> <input id="match_button" type="submit" name="button" value="button" onClick="func_load3()" /> </form> action="?page=matching" means the current page, because i use the single entry in my php application. With the code upon, When i click the button, it redirects to the homepage. And I tried to use: <form name="myform" action="<?php echo $_SERVER['PHP_SELF']; ?>" method="GET"> but it still doesn't work. So i have to ask for help from you. Do you have any ideas about that? How to fix it? Thanks in advance.

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  • Suggest resources for learning Scheme.

    - by EmFi
    I'll be starting a new job soon where Scheme is heavily used. I currently do not know Scheme, but my employer assures me that is not a problem. Regardless I'd like to hit the ground running and have a working knowledge of the language before my start date. So I'm looking for good resources from which to learn Scheme. I have had minimal exposure to functional languages. Really only a small chunk of a course devoted to Haskell. But I have a strong background in procedural and OO and procedural languages. Before it gets requested by a commenter, I am competent with the following languages: C, C++, C#, Java, Perl, Python, and Ruby.

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  • Python unhash value

    - by blah01
    Hi all I am a newbie to the python. Can I unhash, or rather how can I unhash a value. I am using std hash() function. What I would like to do is to first hash a value send it somewhere and then unhash it as such: #process X hashedVal = hash(someVal) #send n receive in process Y someVal = unhash(hashedVal) #for example print it print someVal Thx in advance

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  • Python - from file to data structure?

    - by Seafoid
    Hi, I have large file comprising ~100,000 lines. Each line corresponds to a cluster and each entry within each line is a reference i.d. for another file (protein structure in this case), e.g. 1hgn 1dju 3nmj 8kfn 9opu 7gfb 4bui I need to read in the file as a list of lists where each line is a sublist, thus preserving the integrity of the cluster, e.g. nested_list = [['1hgn', '1dju', '3nmj', '8kfn'], ['9opu', '7gfb'], ['4bui']] My current code creates a nested list but the entries within each list are a single string and not comma separated. Therefore, I cannot splice the list with indices so easily. Any help greatly appreciated. Thanks, S :-)

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  • How to sanely read and dump structs to disk when some fields are pointers?

    - by bp
    Hello, I'm writing a FUSE plugin in C. I'm keeping track of data structures in the filesystem through structs like: typedef struct { block_number_t inode; filename_t filename; //char[SOME_SIZE] some_other_field_t other_field; } fs_directory_table_item_t; Obviously, I have to read (write) these structs from (to) disk at some point. I could treat the struct as a sequence of bytes and do something like this: read(disk_fd, directory_table_item, sizeof(fs_directory_table_item_t)); ...except that cannot possibly work as filename is actually a pointer to the char array. I'd really like to avoid having to write code like: read(disk_df, *directory_table_item.inode, sizeof(block_number_t)); read(disk_df, directory_table_item.filename, sizeof(filename_t)); read(disk_df, *directory_table_item.other_field, sizeof(some_other_field_t)); ...for each struct in the code, because I'd have to replicate code and changes in no less than three different places (definition, reading, writing). Any DRYer but still maintainable ideas?

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  • Coding issue in the 3D Buzz Hyperion tutorial.I am work

    - by Geno
    I'm following along with the tutorial. And we are currently coding the Item class. I am using the 2008 edition, while the tutorial uses 2005. The code I am having issue with is: public string Weight { get { return weight; } set { weight = value; } } earlier in the code, we had: private int Weight = 1; as you can see, they are both different variables, int, and string. I'm doing exactly as the tutorial shows, on mine, I get a conversion error, whereas in the tutorial, there are no errors, why is this? I'm doing exactly what the video shows.

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  • Assigning a value to a variable gets stored in the wrong spot?

    - by scribbloid
    Hello, I'm relatively new to C, and this is baffling me right now. It's part of a much larger program, but I've written this little program to depict the problem I'm having. #include <stdio.h> int main() { signed int tcodes[3][1]; tcodes[0][0] = 0; tcodes[0][1] = 1000; tcodes[1][0] = 1000; tcodes[1][1] = 0; tcodes[2][0] = 0; tcodes[2][1] = 1000; tcodes[3][0] = 1000; tcodes[3][1] = 0; int x, y, c; for(c = 0; c <= 3; c++) { printf("%d %d %d\r\n", c, tcodes[c][0], tcodes[c][1]); x = 20; y = 30; } } I'd expect this program to output: 0 0 1000 1 1000 0 2 0 1000 3 1000 0 But instead, I get: 0 0 1000 1 1000 0 2 0 20 3 20 30 It does this for any number assigned to x and y. For some reason x and y are overriding parts of the array in memory. Can someone explain what's going on? Thanks!

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  • run multiple programs in linux

    - by Betamoo
    I am trying to write a .sh file that runs many programs simultaneously I tried this prog1 prog2 But that runs prog1 then waits until prog1 ends and then starts prog2... So how can I run them in parallel? Thanks

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  • Why won't the following haskell code compile?

    - by voxcogitatio
    I'm in the process of writing a small lisp interpreter in haskell. In the process i defined this datatype, to get a less typed number; data Number = _Int Integer | _Rational Rational | _Float Double deriving(Eq,Show) Compiling this fails with the following error: ERROR "types.hs":16 - Syntax error in data type declaration (unexpected `|') Line 16 is the line w. the first '|' in the code above.

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  • What's the scope of a Python variable declared in an if statement?

    - by froadie
    I'm new to Python, so this is probably a simple scoping question. The following code in a Python file (module) is confusing me slightly: if __name__ == '__main__': x = 1 print x In other languages I've worked in, this code would throw an exception, as the x variable is local to the if statement and should not exist outside of it. But this code executes, and prints 1. Can anyone explain this behavior? Are all variables declared in a module global/available to the entire module?

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  • Java: how to have global values inside a class?

    - by HH
    I want less methods. I want a common global TestClass from which I could use any of its value inside the class. import java.util.*; import java.io.*; public class TestClass { TestClass(String hello){ String hallo = hello; String halloSecond = "Saluto!"; } public static void main(String[] args) { TestClass test = new TestClass("Tjena!"); System.out.println("I want "Tjena!": " + test.hallo); TestClass testSecond = new TestClass("1"); System.out.println("I want Saluto!:" + test.halloSecond); System.out.println("I want Saluto!:" + testSecond.halloSecond); // How can I get glob.vars like the "Saluto!"? } }

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  • sp_help with wildcards

    - by serhio
    There is a command in SqlServer sp_help 'table_name' (table_name or other stuff) Is there a possibility to use it when you don't know the whole table name, with wildcards or something like this: sp_help admin_%

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  • Another dynamic memory allocation bug.

    - by m4design
    I'm trying to allocate memory for a multidimensional array (8 rows, 3 columns). Here's the code for the allocation (I'm sure the error is clear for you) char **ptr = (char **) malloc( sizeof(char) * 8); for (i = 0; i < 3; i++) ptr[i] = (char *) malloc( sizeof(char) * 3); The crash happens when I reference this: ptr[3][0]; Unhandled exception at 0x0135144d in xxxx.exe: 0xC0000005: Access violation writing location 0xabababab. Are there any recommended references/readings for this kind of subject? Thanks.

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  • In DOM is it OK to use .notation for getting/setting attributes?

    - by Ziggy
    Hi In DOM, is it OK to refer to an element's attributes like this: var universe = document.getElementById('universe'); universe.origin = 'big_bang'; universe.creator = null; universe.style.deterministic = true; ? My deep respect for objects and their privacy, and my sense that things might go terribly wrong if I am not careful, makes me want to do everything more like this: var universe = document.getElementById('universe'); if(universe.hasAttribute('origin')) then universe.origin = 'big_bang'; etc... Is it really necessary to use those accessor methods? Of course it may be more or less necessary depending on how certain I am that the elements I am manipulating will have the attributes I expect them to, but in general do the DOM guys consider it OK to use .notation rather than getters and setters? Thanks!

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  • convert string to dict using list comprehension in python

    - by Pavel
    I have came across this problem a few times and can't seem to figure out a simple solution. Say I have a string string = "a=0 b=1 c=3" I want to convert that into a dictionary with a, b and c being the key and 0, 1, and 3 being their respective values (converted to int). Obviously I can do this: list = string.split() dic = {} for entry in list: key, val = entry.split('=') dic[key] = int(val) But I don't really like that for loop, It seems so simple that you should be able to convert it to some sort of list comprehension expression. And that works for slightly simpler cases where the val can be a string. dic = dict([entry.split('=') for entry in list]) However, I need to convert val to an int on the fly and doing something like this is syntactically incorrect. dic = dict([[entry[0], int(entry[1])] for entry.split('=') in list]) So my question is: is there a way to eliminate the for loop using list comprehension? If not, is there some built in python method that will do that for me?

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  • Would it be faster to use CMS for building the first site in ASP.NET?

    - by rem
    I need an opinion and advise from experienced ASP.NET people, what way to go. Assuming that a developer has some practical background with HTML/JavaScript/PHP on one side and some .NET/C#/WPF experience on the other side. No previous hands on experience with ASP.NET - only theory and some read books on the topic. The task is to build ASP.NET web site with User Managment functionality (user authentication, user account, user buying history, user points and so on) and E-commerce functionality with shopping cart, checkout and all needed for this. Is it worth, i.e. will it be faster, more reliable and secure in the result to use a ASP.NET CMS system (for example Sitefinity from Telerik as declared developer friendly) to build such first site? In what case the learning curve will be more steep and it will take more time to achieve similar results? Notes to take into consideration: 1) Price of the CMS matters not very much 2) E-commerce module should be written from scratch in any case (and integrated in case of using CMS) due to very specific requirements

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  • NZEC Run time Error Occured

    - by madan
    import math def gen_caller(a): for z in a: x,y=z if x==1: x=2 if y>=x and y-x<=100000: for i in range(x,y+1): flag=0 for j in range(2,(long(math.sqrt(i))+1)): if(i%j==0): flag=1 break if flag==0: print i print "" n=(int(raw_input())) gen_caller([[(long(raw_input())) for j in range(0,2)] for i in range(0,n) if n<=10])

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