精华内容
下载资源
问答
  • The PPU(a part of the emulator) need a function to write a line buffer to the screen. I had look through the <a href="https://docs.littlevgl.com">LittlevGL documentation</a>. But I can't find the ...
  • <div><p>Is there a File IO method for Line_set, like write_line_set? Similar with write_point_cloud and write_triangle_mesh.</p><p>该提问来源于开源项目:intel-isl/Open3D</p></div>
  • This post summarizes the classes that can be used to write a file. 1. FileOutputStream public static void writeFile1() throws IOException { File fout = new File("out.txt"); FileOutputStream fos = ne...

    This post summarizes the classes that can be used to write a file.

    1. FileOutputStream

    public static void writeFile1() throws IOException {
    	File fout = new File("out.txt");
    	FileOutputStream fos = new FileOutputStream(fout);
    	BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(fos));
    	for (int i = 0; i < 10; i++) {
    		bw.write("something");
    		bw.newLine();
    	}
    	bw.close();
    }
    

    This example use FileOutputStream, instead you can use FileWriter or PrintWriter which is normally good enough for a text file operations.

    2. FileWriter

    public static void writeFile2() throws IOException {
    	FileWriter fw = new FileWriter("out.txt");
    	for (int i = 0; i < 10; i++) {
    		fw.write("something");
    	}
    	fw.close();
    }
    

    3. PrintWriter

    public static void writeFile3() throws IOException {
    	PrintWriter pw = new PrintWriter(new FileWriter("out.txt"));
    	for (int i = 0; i < 10; i++) {
    		pw.write("something");
    	} 
    	pw.close();
    }
    

    4. OutputStreamWriter

    public static void writeFile4() throws IOException {
    	File fout = new File("out.txt");
    	FileOutputStream fos = new FileOutputStream(fout);
    	OutputStreamWriter osw = new OutputStreamWriter(fos);
    	for (int i = 0; i < 10; i++) {
    		osw.write("something");
    	}
    	osw.close();
    }
    

    5. Their Differences

    From Java Doc:

    FileWriter is a convenience class for writing character files. The constructors of this class assume that the default character encoding and the default byte-buffer size are acceptable. To specify these values yourself, construct an OutputStreamWriter on a FileOutputStream.

    PrintWriter prints formatted representations of objects to a text-output stream. This class implements all of the print methods found in PrintStream. It does not contain methods for writing raw bytes, for which a program should use unencoded byte streams.

    The main difference is that PrintWriter offers some additional methods for formatting such as println and printf. In addition, FileWriter throws IOException in case of any I/O failure. PrintWriter methods do not throws IOException, instead they set a boolean flag which can be obtained using checkError(). PrintWriter automatically invokes flush after every byte of data is written. In case of FileWriter, caller has to take care of invoking flush.

    6.Summary

    I recommend some website to learn java basic language:
    www.runoob.com(a lot of tools you can learn)
    how2j.cn(maybe you can learn some latest tools,such as hutools,it`s really very interesting,some course need payment sadly)

    展开全文
  • <div><p>Why is it that there are no file read and write routines to read individual lines from a file, or write individual lines to a file, without having to open and close the file around each line ...
  • ve started using loadMaps:true and this is writing the paths only in the files that had no sourcemap before, but write function is appending a new line at the end of my js files.</p><p>该提问来源于...
  • At the naight of the second day, I thought out a solution for this problem just a moment. Where that problem come from? A paper I read has that simbol like this , I can’t use latex to typeset ...

    I thought this problem about two days! I used the google engine to search some solution to this problem, I have not got the answer, I read the Latex companion carefully about 300 pages, also not get the answer. At the naight of the second day, I thought out a solution for this problem just a moment.

    Where that problem come from? A paper I read has that simbol like this 这里写图片描述, I can’t use latex to typeset that for a presentation.

    Now the problem is solved perfectly by me. The source code for Latex is like this:

    \usepackage{tikz}
    ...
    $\langle x, x \rangle \!\!\!\!\!\!\!\!\!\!\!\!\!\!\tikz{\draw(0pt,0pt) -- (23pt,6pt);}$
    ...

    Note that the compiling order is LaTex –> dvi2ps –> ps2pdf. 采用上面的方法虽然产生了正确的结果,但是文档中插入的eps图片都消失了。

    如果想采用编译顺序LaTex –> dvi2pdf的话,需在\usepackage{tikz}的前面加上\def\pgfsysdriver{pgfsys-dvipdfm.def}这样,图片也保留了,也产生了正确的结果。

    展开全文
  • 逐行编写Python文本文件(write a text file in Python, line by line)我需要逐行写一个文本文件。 此代码逐行打印文本,但只有最后一行存储在result.txt文件中。import reimport fileinputfor line in fileinput....

    逐行编写Python文本文件(write a text file in Python, line by line)

    我需要逐行写一个文本文件。 此代码逐行打印文本,但只有最后一行存储在result.txt文件中。

    import re

    import fileinput

    for line in fileinput.input("test.txt"):

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    print new_str

    open('result.txt', 'w').write(new_str)

    I need to write a text file, line by line. This code is printing a text line by line, but only the last line is stored in the result.txt file.

    import re

    import fileinput

    for line in fileinput.input("test.txt"):

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    print new_str

    open('result.txt', 'w').write(new_str)

    原文:https://stackoverflow.com/questions/18287658

    更新时间:2020-07-11 13:07

    最满意答案

    我不知道为什么你需要fileinput模块, open也可以处理这种情况。

    你的for循环遍历所有行并用新行覆盖 new_str 。 最后一行没有下一行,因此不会被覆盖,因此它是唯一可以保存的行。import re

    test_f = open('test.txt')

    result_f = open('result.txt', 'a')

    for line in test_f:

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    result_f.write(new_str)

    # also, this too, please:

    test_f.close()

    result_f.close()

    即使代码崩溃,您也应该使用with语句自动关闭文件。import re

    with open('test.txt') as test_f, open('result.txt', 'w') as result_f:

    for line in test_f:

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    result_f.write(new_str)

    I don't know why you need the fileinput module, open can handle this case as well.

    Your for-loop goes through all lines and overrides new_str with the new line. The last line has no next line, so it won't be overridden, so it's the only line that will get saved. import re

    test_f = open('test.txt')

    result_f = open('result.txt', 'a')

    for line in test_f:

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    result_f.write(new_str)

    # also, this too, please:

    test_f.close()

    result_f.close()

    You should use the with statement to automatically close your files even when your code crashes. import re

    with open('test.txt') as test_f, open('result.txt', 'w') as result_f:

    for line in test_f:

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    result_f.write(new_str)

    2013-08-17

    相关问答

    这是使用enumerate解决方案: with open("in3.txt") as f:

    lines = f.readlines()

    with open("out.txt", "w") as f1:

    for x, line in enumerate(lines): # Changed to enumerate as per recommendation

    y = x*10

    f1.write("\n00:01:"+str

    ...

    我知道解释如何做这样的事情的一般指导方针是更好的形式,但对于像这样的简单任务,代码本身就说明了,真的...... 我会像这样实现它。 from pprint import pprint # For nicer formatting of the output.

    # For the sake of a self-contained example,

    # the data is inlined here.

    #

    # `f` could be replaced with `open('log.txt'

    ...

    在文件中没有“替换现有行”这样的东西。 对于您想要执行的操作,您必须使用修改后的内容编写新文件,然后使用新文件替换旧文件。 示例代码: with open("old.file") as old, open("new.file", "w") as new:

    for line in old:

    line = modify(line.lstrip())

    new.write(line + "\n")

    os.rename("new.file", "old

    ...

    只需更改您的代码: if( isset($_POST['submit']) ){

    $name = $_POST['name'];

    $age = $_POST['age'];

    $address = $_POST['address'];

    $file = fopen("student.txt","a");

    ...

    我不确定我完全明白你在问什么,但我会尽力帮忙。 如果您尝试从文件中选择随机行,可以使用open() , readlines() , random.choice() : import random

    line = random.choice(open("file").readlines())

    如果您尝试从三个列表中的每一个中选择一个随机元素,则可以使用random.choice() : import random

    choices=[random.choice(i) for i in lists]

    ...

    尝试这个: with open('data.txt') as inf:

    for line in inf:

    num = line.strip()

    if num:

    fn = '%s.txt' %num

    with open(fn, 'w') as outf:

    outf.write('contains one line of text "%s"\n' %num)

    使用with构造函数确

    ...

    python中的文件I / O已经缓冲。 open()函数可以让您确定缓冲写入的范围: 可选的buffering参数指定文件所需的缓冲区大小: 0表示无缓冲, 1表示行缓冲,任何其他正值表示使用(大约)该大小的缓冲区。 负buffering意味着使用系统默认值,通常为tty设备进行行缓冲,并为其他文件进行完全缓冲。 如果省略,则使用系统默认值。 就个人而言,我通过with语句将该文件用作上下文管理器。 只要with suite下的所有语句(至少一个缩进级别更深)已完成或引发异常,文件对象就会关闭:

    ...

    您的代码确实输出换行符。 检查您的编辑器是否识别\n换行符。 但是,它是偶然的。 writelines期望一系列的行: with open('output.txt','w', encoding='UTF-8') as output:

    output.writelines(str(i)+'\n' for i in range(5))

    Your code does output newlines. Check that your editor recognizes \n newlines. How

    ...

    引用文档 , 要从文件中读取行,可以循环遍历文件对象。 这是内存高效,快速,并导致简单的代码 所以,我是你,我会这样做的 import os

    wordReplacements = {'document':'file', 'notepad':'Notepad'}

    def transform_line(line):

    for key, value in wordReplacements.iteritems():

    line = line.replace(key, value)

    ...

    我不知道为什么你需要fileinput模块, open也可以处理这种情况。 你的for循环遍历所有行并用新行覆盖 new_str 。 最后一行没有下一行,因此不会被覆盖,因此它是唯一可以保存的行。 import re

    test_f = open('test.txt')

    result_f = open('result.txt', 'a')

    for line in test_f:

    new_str = re.sub('[^a-zA-Z0-9\n\.]'," ", line)

    result

    ...

    展开全文
  • <div><p>InfluxDB recently introduced a new line protocol write API, for more efficient bulk entry of points: <p>https://github.com/influxdb/influxdb/pull/2696</p> <p>It would be awesome if support for...
  • reference:  http://www.geeksforgeeks.org/write-one-line-c-function-to-find-whether-a-no-is-power-of-two/ Problem Definition: ...Write one line C function to find whether a no is power of two.

    reference: 

    http://www.geeksforgeeks.org/write-one-line-c-function-to-find-whether-a-no-is-power-of-two/


    Problem Definition:

    Write one line C function to find whether a no is power of two.


    Solution:

    If we subtract a power of 2 numbers by 1 then all unset bits after the only set bit become set; and the set bit become unset.

    For example for 4 ( 100) and 16(10000), we get following after subtracting 1
    3 –> 011
    15 –> 01111

    So, if a number n is a power of 2 then bitwise & of n and n-1 will be zero. We can say n is a power of 2 or not based on value of n&(n-1).The expression n&(n-1) will not work when n is 0. To handle this case also, our expression will become n& (!n&(n-1)).


    Code:

    /* Function to check if x is power of 2*/
    bool isPowerOfTwo (int x)
    {
      /* First x in the below expression is for the case when x is 0 */
      return x && (!(x&(x-1)));
    }


    展开全文
  • Text files are structured as a sequence of lines, where each line ... In order to open a file for writing or use in Python, you must rely on the ..., Well, the problem you have is wrong line ending/en...
  • A carriage return sent over usb serial is replaced with a new line character when sent <code>e.g. sys.stdout.write('String\n'), <code>print('String\n', end='')</code> or ...
  • 如何写出好的一流文章,elsevier的一篇报告,还有挺不错的。
  • I want to write a PHP script that I can use from the command line. I want it to prompt and accept input for a few items, and then spit out some results. I want to do this in PHP, because all my classe...
  • <div><p>This PR removes a deprecated encoder with an updated one that simplifies its implementation by moving common functionality into new modules, field_util and line_protocol. As a result, I was ...
  • <div><p>Adds the command line option pair -w/--write. These options indicate that the output should be written to standard output, rather than being posted to coveralls.io, which may be useful for ...
  • <p>I am unable to write data using the line protocol. Here is the code utilised to try and achieve this. <p><strong>Creating the write API:</strong></p> <pre><code>python write_options = ifx....
  • #include <stdio.h> #define State '\n' void main() { int Juge=0;/*only one space*/ int c=0; while((c=getchar())!=EOF) { if(c==' '||c=='\t'||c=='\b') ...

空空如也

空空如也

1 2 3 4 5 ... 20
收藏数 28,140
精华内容 11,256
关键字:

alinewrite