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copied!<p>Based on what you have in your questions, if you are populating pA in a function I suspect you are not changing the contents of pA, which may be the issues. It may be helpful/useful to see the routine you are using to populate pA. </p> <p>C functions call by value if so you are just passing in a pointer (just pA), to change the value of the pointer, you need to pass the address of the pointer (pointer to a pointer if you will). Then you need to deference once it to set the pointer (to the pointer) and then deference it twice to set the values in allocated memory/array.</p> <p>So the calling to the function is </p> <pre><code>void init(File *fpin, double **pA, int lines) { /* Deference once to set the pointer to the pitner */ *pA = (double *)malloc(lines*sizeof(double)); for (int i=0; i<lines; i++) { /* deference twice to set the the element of the pointer to the pointer */ fscanf(fpIn, "%lf", &(**pA)[i]); } } </code></pre> <p>and then in calling the routine, you need to pass in the address of pA. </p> <pre><code>init(fpIn,&pA,lines); </code></pre> <p>Here is a link which might help explain pointers to pointers: <a href="http://www.thegeekstuff.com/2012/01/advanced-c-pointers/" rel="nofollow">http://www.thegeekstuff.com/2012/01/advanced-c-pointers/</a></p> <p>It has been a long time since I have done pointers to pointers, but if you use the above, you may have to make some minor changes.</p> <p>As larsmans is hinting, I like his suggestion of changing the routine to return the pointer to the memory you allocated and place that value in pA. </p> <pre><code>double* init(File *fpin, int lines) { double *local = (double *)malloc(lines*sizeof(double)); //Fills Array for (int i=0; i<lines; i++) { fscanf(fpIn, "%lf", &local[i]); } return(local); </code></pre> <p>}</p> <p>and then in the calling to init</p> <pre><code>pA = init(fpIn,lines); </code></pre> <p>Depending upon what you are trying to accomplish, this may be easier to understand and not quite as complex.</p>

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