Reg：访问3d矩阵的元素 [英] Reg: Accessing elements of 3d matrix

问题描述

大家好，

实际上，我已经从其子标题中读取了一个图像的数据文件，将数据存储在缓冲区中。* imdata是指向数据缓冲区的指针。数据大小为100x100x81，没有。每个像素的字节数是4个字节，格式类型是浮点数。现在我必须阅读第三维中第40行的所有rowa和列。我的问题是如何通过这个指针imdata访问它。在此先感谢。


imsize_x = 100;

imsize_y = 100;

imsize_z = 81;

nobytesperpixel = 4;

我想得到z = 40的所有元素100x100。

Hi all,

Actually, I have read a data file of an image from its sub header stored the data in a buffer.*imdata is a pointer to the buffer for data. The data size is 100x100x81 and no. of bytes per pixel is 4 bytes and the format type is float. Now I have to read all the rowa and columns of 40th row in 3rd dimension. My problem is how to access it through this pointer imdata. Thanks in advance.

imsize_x=100;
imsize_y=100;
imsize_z=81;
nobytesperpixel=4;
I want to get all the elements 100x100 of z=40.

推荐答案

我有点困惑您的问题。

您是否拥有值z = 40并且您想要访问与此值相关的另一组数据？

I am a little confused by your question.
Is it that you have the value z=40 and you want to access another set of data that relates to this value?

您好willakawill，


对不起，如果我清楚了。我只是给你一个我的意思的例子。


例如：a [3] [ 3] [2]

a [] [] [1] = {2,3,4; 1,2,3; 4,5,6};


a [] [] [2] = {1,1,1; 2,2,2; 3,3， 3};


现在我想访问[] [] [2]的所有行和列;


这里我如前所述* imdata指向这个数据缓冲区的指针。现在我想使用imdata访问这些元素，例如：a [] [] [40]。

Hi willakawill,

Sorry if I anot clear.I am just giving you an example of what I meant.

For eg: a[3][3][2]

a[ ][ ][1]={2,3,4; 1,2,3;4,5,6};

a[ ][ ][2]={1,1,1;2,2,2;3,3,3};

Now I would like to access all the rows and columns of a[ ][ ][2];

Here I have pointer to this buffer of data as I have mentioned before *imdata.So now I want to access these elemnts for eg: a[ ][ ] [40] using imdata.

使用两个for循环，使用索引迭代矩阵的前两个维度，在读取数据时迭代40。这样的事情：

Using two for loops, iterate through the first two dimensions of the matrix, using the indexes and 40 when reading data. Something like this:

展开 | 选择 < span class =codeDivider> | Wrap | 行号

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