Search Results

Search found 355 results on 15 pages for 'tuple'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 2/15 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • Berkeley DB tuple with unknown datatype

    - by Ronnie
    I'm working with a Berkeley database (in Java). I need to read a tuple where the sequence is a string, either an int or long, then another string. How can I determine if the tuple holds an int or a long? Depending on what the tuple holds, I'll do one of the following: String s1 = input.readString(); int num1 = input.readInt(); String s2= input.readString(); or String s1 = input.readString(); long num1 = input.readLong(); String s2= input.readString(); The int is 4 bytes and the long is 8 bytes. If the tuple holds an int and I read it in as a long, I get an invalid value as it converts the 4 byte int + 4 bytes of the following string into a long.

    Read the article

  • Using Python tuples as vectors

    - by Etaoin
    I need to represent immutable vectors in Python ("vectors" as in linear algebra, not as in programming). The tuple seems like an obvious choice. The trouble is when I need to implement things like addition and scalar multiplication. If a and b are vectors, and c is a number, the best I can think of is this: tuple(map(lambda x,y: x + y, a, b)) # add vectors 'a' and 'b' tuple(map(lambda x: x * c, a)) # multiply vector 'a' by scalar 'c' which seems inelegant; there should be a clearer, simpler way to get this done -- not to mention avoiding the call to tuple, since map returns a list. Is there a better option?

    Read the article

  • Returning binomal as a tuple

    - by Mike
    I want to save the results of my function binomal_aux to a tuple but I don't have an idea how to, here is my code I have right now. def binomal (n): i=0 for i in range(n): binomal_aux(n,i) #want this to be in a tuple so, binomal (2) = (1,2,1) return def binomal_aux (n,k): if (k==0): return 1 elif (n==k): return 1 else: return (binomal_aux(n-1,k) + binomal_aux(n-1,k-1))

    Read the article

  • What exactly are tuples in Python?

    - by Sergio Tapia
    I'm following a couple of Pythone exercises and I'm stumped at this one. # C. sort_last # Given a list of non-empty tuples, return a list sorted in increasing # order by the last element in each tuple. # e.g. [(1, 7), (1, 3), (3, 4, 5), (2, 2)] yields # [(2, 2), (1, 3), (3, 4, 5), (1, 7)] # Hint: use a custom key= function to extract the last element form each tuple. def sort_last(tuples): # +++your code here+++ return What is a Tuple? Do they mean a List of Lists?

    Read the article

  • Is Boost.Tuple compatible with C++0x variadic templates ?

    - by Thomas Petit
    Hi, I was playing around with variadic templates (gcc 4.5) and hit this problem : template <typename... Args> boost::tuple<Args...> my_make_tuple(Args... args) { return boost::tuple<Args...>(args...); } int main (void) { boost::tuple<int, char> t = my_make_tuple(8, 'c'); } GCC error message : sorry, unimplemented: cannot expand 'Arg ...' into a fixed-length argument list In function 'int my_make_tuple(Arg ...)' If I replace every occurrence of boost::tuple by std::tuple, it compiles fine. Is there a problem in boost tuple implementation ? Or is this a gcc bug ? I must stick with Boost.Tuple for now. Do you know any workaround ? Thanks.

    Read the article

  • Getting error on inserting tuple values in postgreSQL table using python

    - by rahman.bd
    Hello, I want to keep last.fm's user recent music tracks list to postgresql database table using pylast interface.But when I tried to insert values to the table it shows errors.Code example: for i, artist in enumerate(recent_tracks): for key in sorted(artist): cur.execute(""" INSERT INTO u_recent_track(Playback_date,Time_stamp,Track) VALUES (%s,%s)""", (key, artist[key])) conn.commit() cur.execute("SELECT * FROM u_recent_track;") cur.fetchone() for row in cur: print ' '.join(row[1:]) cur.close() conn.close() Here "recent_tracks" tuple have the values for example: artist 0 - playback_date : 5 May 2010, 11:14 - timestamp : 1273058099 - track : Brian Eno - Web I want to store these value under u_recent_track(Tid,Playback_date,Time_stamp,Track).Can anybody have idea how to sort out this problem? when I tried to run, it shows error: Traceback (most recent call last): File "F:\JavaWorkspace\Test\src\recent_track_database.py", line 50, in <module> VALUES (%s,%s,%s)""", (key, artist[key])) IndexError: tuple index out of range Thanks in advanced!

    Read the article

  • Python: Converting a tuple to a string with 'err'

    - by skylarking
    Given this : import os import subprocess def check_server(): cl = subprocess.Popen(["nmap","10.7.1.71"], stdout=subprocess.PIPE) result = cl.communicate() print result check_server() check_server() returns this tuple: ('\nStarting Nmap 4.53 ( http://insecure.org ) at 2010-04-07 07:26 EDT\nInteresting ports on 10.7.1.71:\nNot shown: 1711 closed ports\nPORT STATE SERVICE\n21/tcp open ftp\n22/tcp open ssh\n80/tcp open http\n\nNmap done: 1 IP address (1 host up) scanned in 0.293 seconds\n', None) Changing the second line in the method to result, err = cl.communicate() results in check_server() returning : Starting Nmap 4.53 ( http://insecure.org ) at 2010-04-07 07:27 EDT Interesting ports on 10.7.1.71: Not shown: 1711 closed ports PORT STATE SERVICE 21/tcp open ftp 22/tcp open ssh 80/tcp open http Nmap done: 1 IP address (1 host up) scanned in 0.319 seconds Looks to be the case that the tuple is converted to a string, and the \n's are being stripped.... but how? What is 'err' and what exactly is it doing?

    Read the article

  • Export list as .txt (Python)

    - by Nimbuz
    My Python module has a list that contains all the data I want to save as a .txt file somewhere. The list contains several tuples like so: list = [ ('one', 'two', 'three'), ('four', 'five', 'six')] How do I print the list so each tuple item is separated by a tab and each tuple is separated by a newline? Thanks

    Read the article

  • Using Tuples in Java

    - by syker
    My Hashtable in Java would benefit from a value having a tuple structure. What data structure can I use in Java to do that? Hastable<Long, Tuple<Set<Long>,Set<Long>>> table = ...

    Read the article

  • Why is TRest in Tuple<T1... TRest> not constrained?

    - by Anthony Pegram
    In a Tuple, if you have more than 7 items, you can provide an 8th item that is another tuple and define up to 7 items, and then another tuple as the 8th and on and on down the line. However, there is no constraint on the 8th item at compile time. For example, this is legal code for the compiler: var tuple = new Tuple<int, int, int, int, int, int, int, double> (1, 1, 1, 1, 1, 1, 1, 1d); Even though the intellisense documentation says that TRest must be a Tuple. You do not get any error when writing or building the code, it does not manifest until runtime in the form of an ArgumentException. You can roughly implement a Tuple in a few minutes, complete with a Tuple-constrained 8th item. I just wonder why it was left off the current implementation? Is it possibly a forward-compatibility issue where they could add more elements with a hypothetical C# 5? Short version of rough implementation interface IMyTuple { } class MyTuple<T1> : IMyTuple { public T1 Item1 { get; private set; } public MyTuple(T1 item1) { Item1 = item1; } } class MyTuple<T1, T2> : MyTuple<T1> { public T2 Item2 { get; private set; } public MyTuple(T1 item1, T2 item2) : base(item1) { Item2 = item2; } } class MyTuple<T1, T2, TRest> : MyTuple<T1, T2> where TRest : IMyTuple { public TRest Rest { get; private set; } public MyTuple(T1 item1, T2 item2, TRest rest) : base(item1, item2) { Rest = rest; } } ... var mytuple = new MyTuple<int, int, MyTuple<int>>(1, 1, new MyTuple<int>(1)); // legal var mytuple2 = new MyTuple<int, int, int>(1, 2, 3); // illegal

    Read the article

  • State Monad, why not a tuple?

    - by thr
    I've just wrapped my head around monads (at least I'd like to think I have) and more specifically the state monad, which some people that are way smarter then me figured out, so I'm probably way of with this question. Anyway, the state monad is usually implemented with a M<'a as something like this (F#): type State<'a, 'state> = State of ('state -> 'a * 'state) Now my question: Is there any reason why you couldn't use a tuple here? Other then the possible ambiguity between MonadA<'a, 'b> and MonadB<'a, 'b> which would both become the equivalent ('a * 'b) tuple. Edit: Added example for clarity type StateMonad() = member m.Return a = (fun s -> a, s) member m.Bind(x, f) = (fun s -> let a, s_ = x s in f a s_) let state = new StateMonad() let getState = (fun s -> s, s) let setState s = (fun _ -> (), s) let execute m s = m s |> fst

    Read the article

  • Haskell Input Return Tuple

    - by peterwkc
    Hello to all, i wonder can a IO() function return tuple because i would like to get these out of this function as input for another function. investinput :: IO()->([Char], Int) investinput = do putStrLn "Enter Username : " username <- getLine putStrLn "Enter Invest Amount : " tempamount <- getLIne let amount = show tempamount return (username, amount) Please help. Thanks.

    Read the article

  • Tuple conversion to a string

    - by David542
    I have the following list: [('Steve Buscemi', 'Mr. Pink'), ('Chris Penn', 'Nice Guy Eddie'), ...] I need to convert it to a string in the following format: "(Steve Buscemi, Mr. Pink), (Chris Penn, Nice Guy Eddit), ..." I tried doing str = ', '.join(item for item in items) but run into the following error: TypeError: sequence item 0: expected string, tuple found How would I do the above formatting?

    Read the article

  • SQLAlchemy returns tuple not dictionary

    - by Ivan
    Hi everyone, I've updated SQLAlchemy to 0.6 but it broke everything. I've noticed it returns tuple not a dictionary anymore. Here's a sample query: query = session.query(User.id, User.username, User.email).filter(and_(User.id == id, User.username == username)).limit(1) result = session.execute(query).fetchone() This piece of code used to return a dictionary in 0.5. My question is how can I return a dictionary?

    Read the article

  • Scala return type for tuple-functions

    - by Felix
    Hello Guys, I want to make a scala function which returns a scala tuple. I can do a function like this: def foo = (1,"hello","world") and this will work fine, but now I want to tell the compiler what I expect to be returned from the function instead of using the built in type inference (after all, I have no idea what a (1,"hello","world") is) I thought I remembered the classname being something like Tuple3[Int,String,String] but that doesnt work for me. Suggestions? :D (ps: I love stack overflow!)

    Read the article

  • efficiently convert string (or tuple) to ctypes array

    - by Mu Mind
    I've got code that takes a PIL image and converts it to a ctypes array to pass out to a C function: w_px, h_px = img.size pixels = struct.unpack('%dI'%(w_px*h_px), img.convert('RGBA').tostring()) pixels_array = (ctypes.c_int * len(pixels))(*pixels) But I'm dealing with big images, and unpacking that many items into function arguments seems to be noticeably slow. What's the simplest thing I can do to get a reasonable speedup? I'm only converting to a tuple as an intermediate step, so if it's unnecessary, all the better.

    Read the article

  • Haskell Tuple Size Limit

    - by SHiNKiROU
    Why I can't construct large tuples in Haskell? Why there's a tuple size limit? Prelude> (1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1) <interactive>:1:0: No instance for (Show (t, t1, t2, ... t23)) arising from a use of `print' at <interactive>:1:0-48 Possible fix: add an instance declaration for (Show (t, t1, t2, ... t23)) In a stmt of a 'do' expression: print it

    Read the article

  • Python 3.1.1 Problem With Tuples

    - by Protean
    This piece of code is supposed to go through a list and preform some formatting to the items, such as removing quotations, and then saving it to another list. class process: def rchr(string_i, asciivalue): string_o = () for i in range(len(string_i)): if ord(string_i[i]) != asciivalue: string_o += string_i[i] return string_o def flist(self, list_i): cache = () cache_list = [] for line in list_i: cache = line.split('\t') cacbe[0] = process.rchr(str(cache[0]), 34) cache_list.append(cache[0]) cache_list[index] = cache index += 1 cache_list.sort() return cache_list p = process() list1a = ['cow', 'dog', '"sheep"'] list1 = p.flist(list1a) print (country_list) However; it chokes at 'string_o += string_i[i]' and gives the following error: Traceback (most recent call last): File "/Projects/Python/safafa.py", line 23, in <module> list1 = p.flist(list1a) File "/Projects/Python/safafa.py", line 14, in flist cacbe[0] = process.rchr(str(cache[0]), 34) File "/Projects/Python/safafa.py", line 7, in rchr string_o += string_i[i] TypeError: can only concatenate tuple (not "str") to tuple

    Read the article

  • Tuple struct constructor complains about private fields

    - by Grubermensch
    I am working on a basic shell interpreter to familiarize myself with Rust. While working on the table for storing suspended jobs in the shell, I have gotten stuck at the following compiler error message: tsh.rs:8:18: 8:31 error: cannot invoke tuple struct constructor with private fields tsh.rs:8 let mut jobs = job::JobsList(vec![]); ^~~~~~~~~~~~~ It's unclear to me what is being seen as private here. As you can see below, both of the structs are tagged with pub in my module file. So, what's the secret sauce? tsh.rs use std::io; mod job; fn main() { // Initialize jobs list let mut jobs = job::JobsList(vec![]); loop { /*** Shell runtime loop ***/ } } job.rs use std::fmt; pub struct Job { jid: int, pid: int, cmd: String } impl fmt::Show for Job { /*** Formatter ***/ } pub struct JobsList(Vec<Job>); impl fmt::Show for JobsList { /*** Formatter ***/ }

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >