file-io

问题 I'm trying to develop a multithreaded java program for split a large text file into smaller text files. The smaller files created must have a prefixed number of lines. For example: if the number of lines of input file is 100 and the input number is 10, the result of my program is to split the input file into 10 files. I've already developed a singlethreaded version of my program: import java.io.BufferedReader; import java.io.File; import java.io.FileNotFoundException; import java.io

问题 I am generating xml file using "from xml.etree import ElementTree" and placing the generated output in to a new file "test.xml". The output is getting placed inside the test.xml but there is no new line its a big big line. So, what shall i do to have new line inside "test.xml" . Following is the script: from xml.etree import ElementTree from xml.dom import minidom from lxml import etree def prettify(elem): """Return a pretty-printed XML string for the Element. """ rough_string = ElementTree

问题 I am generating xml file using "from xml.etree import ElementTree" and placing the generated output in to a new file "test.xml". The output is getting placed inside the test.xml but there is no new line its a big big line. So, what shall i do to have new line inside "test.xml" . Following is the script: from xml.etree import ElementTree from xml.dom import minidom from lxml import etree def prettify(elem): """Return a pretty-printed XML string for the Element. """ rough_string = ElementTree

问题 I have a glitch in my program that causes a question mark (\u003f) to appear in the sixth (index = 5) slot in strings when I encrypt them. Normally, this is reversed upon decryption. However, it is not reversed if I save the string to a file first. I have determined that when I save a string containing Unicode characters to a file, I will not be able to determine the correct length for the file. I have managed to reproduce the glitch in the following function... public static void testFileIO

问题 I have a problem but I feel the solution should be quite simple. I'm building a model and want to test its accuracy by 10-fold cross-validation. To do this I have to split my training corpus 90%/10% into training and test sections, then train my model on the 90% and test on the 10%. This I want to do ten times, by taking a different 90%/10% split every time, so that eventually each bit of the corpus has been used as testing data. Then I'll average the results for each 10% test. I have tried

问题 I'm trying to write a program, when the program is performing an operation (Example: search, update, or add), it should be direct access. The program should not read all the records sequentially to reach a record. #include <iostream> #include <fstream> #include <string> using namespace std; struct Student{ int Id; int Money; int Age; char name[15]; }; void main(){ Student buffer; ofstream BinaryFile("student", ios::binary); ifstream WorkerText("worker.txt"); //--------------------------------

问题 I'm trying to write a program, when the program is performing an operation (Example: search, update, or add), it should be direct access. The program should not read all the records sequentially to reach a record. #include <iostream> #include <fstream> #include <string> using namespace std; struct Student{ int Id; int Money; int Age; char name[15]; }; void main(){ Student buffer; ofstream BinaryFile("student", ios::binary); ifstream WorkerText("worker.txt"); //--------------------------------

问题 Using textscan I'm trying to read a file that has comma separated data in the following format: "1234","24.0","Hello, my name is Joe" "4567","25,0","Hi, I'm Jane" The non-delimiter comma in the third field are problematic and I ultimately don't want the "" around the pieces of data. I've tried the following, but it leaves a " on the end of the last field. I can remove this any number of ways, but I find it quite annoying and am sure there is a smarter way. Any ideas? textscan(fileId, '"%s %s

问题 I'm very new to pointers and linked lists but I'm trying to write a simple program that reads in data from a text file into a linked list. I'm having trouble with the input function. It looks like this: DVDNode* CreateList(string fileName) { ifstream inFile; inFile.open(fileName.c_str()); DVDNode* head = NULL; DVDNode* dvdPtr; dvdPtr = new DVDNode; while(inFile && dvdPtr != NULL) { getline(inFile, dvdPtr -> title); getline(inFile, dvdPtr -> leadActor); getline(inFile, dvdPtr ->

问题 The simple fopen operation seems to not work. perror returns - Invalid argument. What could be wrong. I have a ascii file called abc.dat in R:. int main() { FILE *f = fopen("R:\abc.dat","r"); if(!f) { perror ("The following error occurred"); return 1; } } Output: The following error occurred: Invalid argument. 回答1: Escape your \ . It must be \\ when used in the string. FILE *f = fopen("R:\\abc.dat","r"); Otherwise, the string is seen by fopen to be including the \a "alert" escape sequence