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    <p>Don't de-reference <code>centroid</code> when passing in. Doing that will only pass your first row. Do this:</p> <pre><code>initialize_centroids( centroid, noofcentroids, newnoofvar ); </code></pre> <p>Then you need to use the correct type here:</p> <pre><code>void initialize_centroids( int **carray, int p, int q ) </code></pre> <p>Your array is presumably an <code>int**</code>. That means it's a pointer to a location in memory that contains an array of <code>int*</code> pointers. Each of those pointers (I assume) references memory that has been allocated one row of your array.</p> <p>Now, once you obtain one of these pointers by doing <code>carray[i]</code> you have selected row <code>i</code>. You now have an <code>int*</code> which means it points to an array of <code>int</code>.</p> <p>Finally, <code>carray[i][j]</code> selects a specific integer from column <code>j</code> on row <code>i</code>.</p> <p><em>[edit]</em></p> <p>Theory about what might be going wrong... You may not be allocating a 2D array in a dynamic sense, or indeed it might be a 1D array and you are supposed to use stride-lengths etc. Here is a solution that you can use for allocating a 2D array dynamically, and indexing it as <code>carray[i][j]</code>.</p> <p><em>Note: Some people have gotten upset at me for this method in the past due to alignment concerns, but I have never had issues. I think they were just having a grumpy day. For those who are worried about alignment, it's easy to adjust for that, but is too complicated for this example.</em></p> <pre><code>int** allocate_array2d( int rows, int cols ) { int i, **arr, *data; arr = (int**)malloc( rows * sizeof(int*) + rows*cols*sizeof(int) ); data = (int*)(arr + rows); for( i = 0; i &lt; rows; i++ ) { rows[i] = data; data += cols; } return arr; } void free_array2d( int** arr ) { free((void*)arr); } </code></pre> <p>Now, in your main:</p> <pre><code>int** centroid = allocate_array2d( noofcentroids, newnoofvar ); initialize_centroids( centroid, noofcentroids, newnoofvar ); </code></pre> <p><em>[more...]</em></p> <blockquote> <p>Okay.Yes I allocated memory like this centroid[100][100] – Bobby 11 mins ago</p> </blockquote> <p>In that case, you should declare:</p> <pre><code>void initialize_centroids( int carray[100][100], int p, int q ) { //... } </code></pre> <p>No need to use my dynamic array example</p>
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    1. POInvalid types int[int] for array subscript
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    1. COI have done the same way.But still I get an error.
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    2. COOh, it appears you have declared the array on the stack and are using it as if it was declared on the heap. Does the array have fixed-size (*ie* hard-coded) dimensions? I will post code for dynamic allocation.
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    3. COOkay.Yes I allocated memory like this centroid[100][100]
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