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https://software.intel.com/en-us/recent/241777
enWin32 compile problem
https://software.intel.com/en-us/forums/intel-math-kernel-library/topic/684921
<p>I am compiling a very simple Dll that uses the Intel MKL libraries. I am using Visual studio 2015 Community edition and Intel MKL 2017 (just released). If I compile using X64 there is no problem and the Dll works fine with other code. If I set it to Win32, I get the error message as shown on the attached screenshot. The .target files have entries that are not in the .target files of the X64 version. Any idea where things went wrong? Regards Karl Eschberger</p>
Thu, 08 Sep 16 04:30:09 -0700Karl Eschberger684921Premier support product selection
https://software.intel.com/en-us/forums/intel-software-development-products-download-registration-licensing/topic/670076
<p>Hi</p>
<p>I have a serial number that I wish to reclaim from a user that has left our company, and transfer it to another user.</p>
<p>I am trying to open a ticket in the Premier support portal, but on the first page "Select Contact and Product", I cannot get any products to appear in the search or in the Browse Products window, either under Product Catalog or Platform Catalog. Clicking either catalog link shows a brief loading icon, but no product list is displayed.</p>
<p>I have tried with both IE11 and Opera.</p>
<p>Any suggestions on how to proceed?</p>
Mon, 18 Jul 16 07:36:37 -0700Alan Ritchie670076FEAST solver missing eigenvalues
https://software.intel.com/en-us/forums/intel-math-kernel-library/topic/610263
<p>I am solving a sparse eigenvalue problem between e<sub>min</sub> and e<sub>max</sub>. When I use a subset of this range, I find extra eigenvalues.</p>
<p> Attached is the test program and matrices. The test program output is</p>
<pre class="brush:plain;">Intel(R) Math Kernel Library Version 11.3.1 Product Build 20151021 for 32-bit applications
Searching between -10 and -0.1
Found 14 eigenvalues:
-0.834635 (1.19813)
-0.656935 (1.52222)
-0.464994 (2.15057)
-0.458775 (2.17972)
-0.436459 (2.29116)
-0.429403 (2.32881)
-0.394109 (2.53737)
-0.391432 (2.55473)
-0.356238 (2.80711)
-0.349315 (2.86275)
-0.304226 (3.28703)
-0.298108 (3.35449)
-0.266397 (3.75379)
-0.24941 (4.00946)
eps=-5.89044
Searching between -10 and -0.4
Found 12 eigenvalues:
-1.83242 (0.545725)
-1.74229 (0.573959)
-1.39579 (0.71644)
-1.07728 (0.92826)
-0.995946 (1.00407)
-0.834693 (1.19805)
-0.657065 (1.52192)
-0.526781 (1.89832)
-0.465162 (2.14979)
-0.458787 (2.17966)
-0.436485 (2.29103)
-0.429825 (2.32653)
eps=-10.8525</pre><p>Where the number in brackets is (-1/λ), as I am solving the inverse of the actual problem. For this application, I am most interested in the lowest result, so returning 1.19 rather than 0.54 is a substantial error.</p>
<p> Matlab, and the textbook solution, both agree with the second set. Is there anything in the MKL that can give me confidence I have actually found the lowest solution? My concern is that iterating up through smaller search intervals will both cost performance, and could potentially still be missing solutions if I cannot get the size of interval.</p>
<p> </p>
Wed, 17 Feb 16 10:20:47 -0800Alan Ritchie610263Feast solver - internal memory error
https://software.intel.com/en-us/forums/intel-math-kernel-library/topic/474787
<p>Hi all.</p>
<p>Calling dfeast_scsrgv, it returns with info=-1, an internal memory error.</p>
<p>The output is </p>
<blockquote><p>Extended Eigensolvers: Size subspace 10</p>
<p>Extended Eigensolvers: Resize subspace 0</p>
<p>Extended Eigensolvers: Error with Internal memory allocation</p>
</blockquote>
<p>I don't know if the error message is accurate, I am using the 64-bit version (11.1.0.103, Windows), and the matrices are pretty small, so it would need to be allocating a huge amount of memory to run out of address space. </p>
<p>Is it trying to create a temporary file - my C: drive is a SSD without much space left? Changing the program working directory to E: does not help, so is it creating a file in a specific location?</p>
<p>Is it a problem with the matrices - the Extended Eigensolver Functionality page in the help says A should be real symmetric, and B should be real symmetric positive definite - I don't have these, I have real symmetric positive definite, and B is real symmetric, about half of the rows in B (and corresponding columns) are zero, ie it could be reordered to <img src="http://latex.codecogs.com/png.latex?%5Cbegin%7Bbmatrix%7D%20B%20%26%200%5C%5C%200%20%26%200%20%5Cend%7Bbmatrix%7D" height="44" width="50" /> - this isn't positive definite, the submatrix isn't either, so should return an error of -3? But it seems to solve this for a different search range of eigenvalues (possibly the change makes some internally generated matrix much larger?)</p>
<p>Mathematically, the zeroes in the B matrix should give eigenvalues of +inf, and an eigenvector that is +1 for the entry corresponding to the matrix row, and zero for all other values, for each row/column that is zero. The other eigenvalues can be found by generating a modified A matrix - I dont know if the FEAST solver will do this internally, and solve the modified problem, or if these eigenvalues all get rejected because the search range is bounded, and the solver just works without B actually being positive definite.</p>
<p>The alternative is to solve the reverse problem, swapping A and B, and solving for 1/λ, but then the range of eigenvalues gets inverted, and I need to find the largest instead of the smallest. I might use ARPACK or something for this, FEAST doesnt seem particularly well suited for finding the largest.</p>
<p>Attached is a test program, and the a, b matrices. If changed to search a different range, test program will find 4 eigenvalues around 182.9, then another 4 around 228.</p>
<p>The benchmark I am testing against suggests I should find a couple of eigenvalues between 1 and 5, but I don't have access to Matlab to check my matrices directly, so the difference might be the matrices I am solving.</p>
<p> So, questions are:</p>
<ol>
<li>Is the out of memory error message correct, or is it a different problem?</li>
<li>Does B have to be positive definite?</li>
<li>Should I always be getting an error message with any matrix of this shape?</li>
<li>Are the values found accurate, or is B not being pos def causing FEAST to find a totally wrong solution?</li>
</ol>
<p>Thanks,</p>
<p>Alan</p>
<p> </p>
Wed, 25 Sep 13 11:08:35 -0700Alan Ritchie474787Eigenvalue solver dfeast_scsrgv overwrites input arguments?
https://software.intel.com/en-us/forums/intel-math-kernel-library/topic/392021
<p> </p>
<p>Experimenting with the symetric general eigen value solver dfeast_scsrgv.</p>
<p>Running it with a test matrix, I find that it overwrites the values for e and x on the stack?</p>
</p>
<p>dfeast_scsrgv (&uplo, &n, a, rows, columns, <br />b, rows, columns, <br />fpm, &epsout, &loop, &emin, &emax, &m0, eigs, eigv, &m, &res, &info);</p>
<p>exits with info=0, m=1, suggesting one eigenvalue was found but eigs and eigv have been changed and no longer point to the original arrays.</p>
</p>
<p>inputs are declared as</p>
<p>double* a = (double*) mkl_malloc(nnz*sizeof(double), MKL_ALIGN);<br />double* b = (double*) mkl_malloc(nnz*sizeof(double), MKL_ALIGN);<br />int* columns = (int*) mkl_malloc(nnz*sizeof(int), MKL_ALIGN);<br />int* rows = (int*) mkl_malloc((n+1)*sizeof(int), MKL_ALIGN);</p>
<p>char uplo = 'U'; //upper triangular matrices</p>
<p>MKL_INT fpm[128];<br />feastinit(fpm);</p>
<p>MKL_INT m0 = 60;<br />double emin = 2;<br />double emax = 150;</p>
<p>//output<br />double epsout = 0, res = 0;<br />double *eigs = (double*) mkl_malloc(m0 * sizeof(double), MKL_ALIGN);<br />double *eigv = (double*) mkl_malloc(m0 * n * sizeof(double), MKL_ALIGN);<br />MKL_INT loop=0, m=0, info = 0;</p>
</p>
<p>Setting a data breakpoint suggests it happens at mkl_core.dll!000007fee5371abf() </p>
<p>I thought I had the wrong size for one of the arguments, but they look ok, and there doesn't appear to be a variable adjacent on the stack.</p>
<p>Test project is attached, VS2010 with MKL 11.0.3</p>
<p>Anyone seen anything similar?</p>
</p>
<p> </p>
</p>
<p> </p>
</p>
<p> </p>
</p>
<p> </p>
<p> </p>
Fri, 03 May 13 11:29:56 -0700Alan Ritchie392021