# Community Q&A and How To **URL:** https://uqworld.org/c/uq-with-uqlab/community-q-a-howto/11.md?page=3 [Latest](https://uqworld.org/latest.md) · [Categories](https://uqworld.org/categories.md) · [Tags](https://uqworld.org/tags.md) **Page:** 4 --- ## [UQLink: ANSYS APDL](https://uqworld.org/t/uqlink-ansys-apdl/2023)
**Author:** [@Mr121Tony](https://uqworld.org/u/Mr121Tony)\ **Replies:** 0\ **Last updated:** [November 9, 2023, 4:46pm UTC](https://uqworld.org/t/uqlink-ansys-apdl/2023 "2023-11-09T16:46:56Z")
Dear Pro. I tried to integrate UQLink and ANSYS APDL. UQLab can calculate each input file and get the output file. But when reading the specified data, it always shows "Third party software returned an error for run #2: … --- ## [Number of Dimensions Must be a Positive Number error](https://uqworld.org/t/number-of-dimensions-must-be-a-positive-number-error/1532)
**Author:** [@Uche\_A](https://uqworld.org/u/Uche_A)\ **Replies:** 2\ **Last updated:** [October 17, 2023, 12:28pm UTC](https://uqworld.org/t/number-of-dimensions-must-be-a-positive-number-error/1532 "2023-10-17T12:28:39Z")
I am trying to scale my UQlab Inversion for larger problems with multiple (space dependent) outputs. I have stacked two output variables to end up with N\_{outputs} = 1534. Before doing any advanced analysis, I wanted to… --- ## [PCE frequency-dependent output with FEM software](https://uqworld.org/t/pce-frequency-dependent-output-with-fem-software/2002)
**Author:** [@Soraya](https://uqworld.org/u/Soraya)\ **Replies:** 2\ **Last updated:** [October 17, 2023, 8:37am UTC](https://uqworld.org/t/pce-frequency-dependent-output-with-fem-software/2002 "2023-10-17T08:37:53Z")
Hello I have 7 uncertain variables in my finite element model and I’m interested in the sound transmission loss of a structure. I work between 89 Hz and 1122 Hz. I get the results of my true model thanks to a commercial… --- ## [Problem in creating a Sequential Polynomial Chaos kriging](https://uqworld.org/t/problem-in-creating-a-sequential-polynomial-chaos-kriging/1998)
**Author:** [@SimoneRomani12](https://uqworld.org/u/SimoneRomani12)\ **Replies:** 2\ **Last updated:** [October 12, 2023, 8:10am UTC](https://uqworld.org/t/problem-in-creating-a-sequential-polynomial-chaos-kriging/1998 "2023-10-12T08:10:41Z")
Dear all, I have some problem in creating a SPCK of a test-function: The code I used is: clearvars rng(100,‘twister’) uqlab ModelOpts.mString = ‘X.\*sin(X).\*cos(X)’; ModelOpts.isVectorized = true; myModel = uq\_cre… --- ## [Uqlink and Nastran](https://uqworld.org/t/uqlink-and-nastran/1694)
**Author:** [@Irma](https://uqworld.org/u/Irma)\ **Replies:** 14\ **Last updated:** [October 10, 2023, 1:55pm UTC](https://uqworld.org/t/uqlink-and-nastran/1694 "2023-10-10T13:55:15Z")
Hello all, I would like to use UqLink with NASTRAN software. But it requires a very specific format for the .bdf file (the file that UqLink must change for each running realisation). Is it possible to furnish this forma… --- ## [Beam problem:PCE surrogate model based calibration, how to give reasonable predictive posterior on multiple points?](https://uqworld.org/t/beam-problem-pce-surrogate-model-based-calibration-how-to-give-reasonable-predictive-posterior-on-multiple-points/1960)
**Author:** [@ny123](https://uqworld.org/u/ny123)\ **Replies:** 4\ **Last updated:** [September 23, 2023, 9:32pm UTC](https://uqworld.org/t/beam-problem-pce-surrogate-model-based-calibration-how-to-give-reasonable-predictive-posterior-on-multiple-points/1960 "2023-09-23T21:32:06Z")
Hi! Everyone. I am doing a classic simply-support-beam question. The input variables are Elastic modulus E and loading position \\delta. I need to create my PCE surrogate model and doing Bayesian inference based on the… --- ## [I am trying to apply different sampling methods for a function but I am only able to use the Monte Carlo method, the others do not work](https://uqworld.org/t/i-am-trying-to-apply-different-sampling-methods-for-a-function-but-i-am-only-able-to-use-the-monte-carlo-method-the-others-do-not-work/1989)
**Author:** [@SimoneRomani12](https://uqworld.org/u/SimoneRomani12)\ **Replies:** 6\ **Last updated:** [September 19, 2023, 1:24pm UTC](https://uqworld.org/t/i-am-trying-to-apply-different-sampling-methods-for-a-function-but-i-am-only-able-to-use-the-monte-carlo-method-the-others-do-not-work/1989 "2023-09-19T13:24:50Z")
I am trying to use the Monte Carlo, Sobol, Halton and Latin hipercube sampling strategies for a test function written by me. Monte Carlo method works but the others sampling methods not and I do not understand what is t… --- ## [I got this message "Error using HC\_35 (line 140) Dimensions of matrices being concatenated are not consistent."](https://uqworld.org/t/i-got-this-message-error-using-hc-35-line-140-dimensions-of-matrices-being-concatenated-are-not-consistent/1984)
**Author:** [@Murat\_Alper\_BASARAN](https://uqworld.org/u/Murat_Alper_BASARAN)\ **Replies:** 1\ **Last updated:** [September 13, 2023, 5:01pm UTC](https://uqworld.org/t/i-got-this-message-error-using-hc-35-line-140-dimensions-of-matrices-being-concatenated-are-not-consistent/1984 "2023-09-13T17:01:01Z")
Hello Dear UQLab users I have 35 independent variables and 1 dependent variables, the data matrix is 28x35. Why did I get this meesage I did not figured it out. Can you help? The code is below: Best Regards uqlab; co… --- ## [Help with understanding UQLAB application to sample case](https://uqworld.org/t/help-with-understanding-uqlab-application-to-sample-case/1954)
**Author:** [@Ljuli2](https://uqworld.org/u/Ljuli2)\ **Replies:** 1\ **Last updated:** [July 26, 2023, 7:17am UTC](https://uqworld.org/t/help-with-understanding-uqlab-application-to-sample-case/1954 "2023-07-26T07:17:08Z")
Hello All, I am looking for a Uncertainty Quantification software that can has various capabilities required. I am looking into UQLAB as a platform to satisfy this search. It would be great if anyone here can take a look… --- ## [Choice of sampling type for regression-based PCE](https://uqworld.org/t/choice-of-sampling-type-for-regression-based-pce/1953)
**Author:** [@achille](https://uqworld.org/u/achille)\ **Replies:** 1\ **Last updated:** [July 24, 2023, 3:42pm UTC](https://uqworld.org/t/choice-of-sampling-type-for-regression-based-pce/1953 "2023-07-24T15:42:23Z")
Hello, I have a general question about regression-based PCE model building: are there any general guidelines on how to select the type of experimental sample (e.g. LHS, Sobol, Monte-Carlo, etc.) used when constructing a… --- ## [How to correctly calculate the ODEs model in UQlab and further complete the sensitivity analysis?](https://uqworld.org/t/how-to-correctly-calculate-the-odes-model-in-uqlab-and-further-complete-the-sensitivity-analysis/1943)
**Author:** [@li\_chaoqun](https://uqworld.org/u/li_chaoqun)\ **Replies:** 3\ **Last updated:** [July 24, 2023, 7:11am UTC](https://uqworld.org/t/how-to-correctly-calculate-the-odes-model-in-uqlab-and-further-complete-the-sensitivity-analysis/1943 "2023-07-24T07:11:12Z")
Hello everyone. I’m new UQ man. I tried using UQlab to compute the ODE model in the attachment and then wanted to be able to analyze it for uncertain input sensitivity. I refer to Dr. Damar’s detailed answer at ‘‘https:… --- ## [Kriging with FEM commercial software](https://uqworld.org/t/kriging-with-fem-commercial-software/1937)
**Author:** [@Soraya](https://uqworld.org/u/Soraya)\ **Replies:** 5\ **Last updated:** [July 17, 2023, 3:09pm UTC](https://uqworld.org/t/kriging-with-fem-commercial-software/1937 "2023-07-17T15:09:36Z")
Hello I’m trying to apply kriging to a finite element model of a simply supported plate subjected to a pressure of 1 Pa. I’m interested in the sound transmission loss of this plate using Actran software. I have three un… --- ## [Multilevel uncertainty quantification with Bayesian inversion](https://uqworld.org/t/multilevel-uncertainty-quantification-with-bayesian-inversion/1705)
**Author:** [@Irma](https://uqworld.org/u/Irma)\ **Replies:** 6\ **Last updated:** [July 14, 2023, 3:03pm UTC](https://uqworld.org/t/multilevel-uncertainty-quantification-with-bayesian-inversion/1705 "2023-07-14T15:03:00Z")
Hello all, I am trying to solve the Bayesian multilevel model updating approach, which was presented by Nagel and Sudret in \[1\]. I am applying the example of the paper (Section 8) using the marginalised formulation prop… --- ## [RBDO error based on data-driven surrogate](https://uqworld.org/t/rbdo-error-based-on-data-driven-surrogate/1926)
**Author:** [@AmosJoseph](https://uqworld.org/u/AmosJoseph)\ **Replies:** 6\ **Last updated:** [July 3, 2023, 11:27am UTC](https://uqworld.org/t/rbdo-error-based-on-data-driven-surrogate/1926 "2023-07-03T11:27:22Z")
PCE\_RBDO.m (3.4 KB) RBDO.m (2.0 KB) Hi, I build a PCE and conduct RBDO based on PCE. I use PCE for the probabilistic constraint. Above PCE\_RBDO.m is the built PCE. RBDO.m is code for RBDO. Below is the error. Could yo… --- ## [Questions about obtaining the statistical moments of PCE model](https://uqworld.org/t/questions-about-obtaining-the-statistical-moments-of-pce-model/1925)
**Author:** [@zhangshengwang](https://uqworld.org/u/zhangshengwang)\ **Replies:** 1\ **Last updated:** [July 1, 2023, 1:16am UTC](https://uqworld.org/t/questions-about-obtaining-the-statistical-moments-of-pce-model/1925 "2023-07-01T01:16:30Z")
Hi everyone, I am very honor to join the community of UQLab. Recently, I came across a problem about the PCE model. I am looking forward to the answer. I would like to obtain the first four moments of PCE model. I have… --- ## [How to show the verbosity information of creating a PCE model](https://uqworld.org/t/how-to-show-the-verbosity-information-of-creating-a-pce-model/1930)
**Author:** [@zhangshengwang](https://uqworld.org/u/zhangshengwang)\ **Replies:** 2\ **Last updated:** [June 29, 2023, 1:34pm UTC](https://uqworld.org/t/how-to-show-the-verbosity-information-of-creating-a-pce-model/1930 "2023-06-29T13:34:11Z")
Hi everyone, I want to obtain verbosity information of creating a PCE model. I found a switch in uq\_PCE\_calculate\_coefficients.m, the code is in lines 17 & 18: % Verbosity level DisplayLevel = current\_model.Internal.D… --- ## [Inserting a Kriging model into LSF for MC reliability analysis](https://uqworld.org/t/inserting-a-kriging-model-into-lsf-for-mc-reliability-analysis/1929)
**Author:** [@a7m3dbalushi](https://uqworld.org/u/a7m3dbalushi)\ **Replies:** 1\ **Last updated:** [June 28, 2023, 3:56pm UTC](https://uqworld.org/t/inserting-a-kriging-model-into-lsf-for-mc-reliability-analysis/1929 "2023-06-28T15:56:25Z")
Hello, I have built a Kriging model which will give me an output for a variable that I will use in a limit state function, I want to perform reliability analysis for the limit state function by MCS. I do not know how to… --- ## [Theoretical doubts about PCE UQLAB](https://uqworld.org/t/theoretical-doubts-about-pce-uqlab/1927)
**Author:** [@Juliana\_Maia](https://uqworld.org/u/Juliana_Maia)\ **Replies:** 2\ **Last updated:** [June 28, 2023, 12:31am UTC](https://uqworld.org/t/theoretical-doubts-about-pce-uqlab/1927 "2023-06-28T00:31:38Z")
Dear all, good afternoon. I hope you are doing well. I am from Brazil, a master’s student in engineering. I am building a metamodel and have one more question. Are the “mean value” data in the output of PCE relative to y… --- ## [Is it possible to use uqlink with a text editor?](https://uqworld.org/t/is-it-possible-to-use-uqlink-with-a-text-editor/1922)
**Author:** [@IHM](https://uqworld.org/u/IHM)\ **Replies:** 0\ **Last updated:** [June 22, 2023, 2:10pm UTC](https://uqworld.org/t/is-it-possible-to-use-uqlink-with-a-text-editor/1922 "2023-06-22T14:10:38Z")
I use software (Castem) which allows me to create a new executable to take into account the mechanical model that I have implemented. To use the new executable I go through a text editor which calls the command (castem21… --- ## [UQLink returning NaN in output: could it be because the command to execute the third party software does not explicitly specify input and output files?](https://uqworld.org/t/uqlink-returning-nan-in-output-could-it-be-because-the-command-to-execute-the-third-party-software-does-not-explicitly-specify-input-and-output-files/1867)
**Author:** [@elisara1000](https://uqworld.org/u/elisara1000)\ **Replies:** 10\ **Last updated:** [June 21, 2023, 8:27am UTC](https://uqworld.org/t/uqlink-returning-nan-in-output-could-it-be-because-the-command-to-execute-the-third-party-software-does-not-explicitly-specify-input-and-output-files/1867 "2023-06-21T08:27:38Z")
I am linking a third party software to UQLabs using UQLink. The third party software is called Hi-sAFe which is used to simulate interactions between trees and crops for agriculture. The software uses multiple input file… --- ## [UQlink with Opensees problem](https://uqworld.org/t/uqlink-with-opensees-problem/1038)
**Author:** [@Ziead\_Metwally](https://uqworld.org/u/Ziead_Metwally)\ **Replies:** 8\ **Last updated:** [June 19, 2023, 7:10am UTC](https://uqworld.org/t/uqlink-with-opensees-problem/1038 "2023-06-19T07:10:52Z")
Hello, I am trying to regenerate the opensees pushover analysis example (example 3, UQLink). However, the simulations are not performed and the following warning is shown. Could anybody help with that? Note that I did… --- ## [Bayesian inference: the Gelman-Rubin value](https://uqworld.org/t/bayesian-inference-the-gelman-rubin-value/1910)
**Author:** [@Mr121Tony](https://uqworld.org/u/Mr121Tony)\ **Replies:** 1\ **Last updated:** [June 15, 2023, 1:16am UTC](https://uqworld.org/t/bayesian-inference-the-gelman-rubin-value/1910 "2023-06-15T01:16:48Z")
Dear Prof, When using Bayesian inference to calibrate model parameters, AIES method is adopted. By adjusting the a value, it is difficult for the Gelman-Rubin value to be less than 1.1 and greater than 1.0. It’s always … --- ## [RBDO: a problem](https://uqworld.org/t/rbdo-a-problem/1881)
**Author:** [@Mr121Tony](https://uqworld.org/u/Mr121Tony)\ **Replies:** 3\ **Last updated:** [June 8, 2023, 9:00am UTC](https://uqworld.org/t/rbdo-a-problem/1881 "2023-06-08T09:00:50Z")
Dear Professors, This problem occurs when I use the Kriging and QMC methods in the RBDO module: " Starting Quantile Monte Carlo (QMC) optimization approach… Initial point is not feasible. Searching for a new one by ra… --- ## [Copula not working with inverse analysis](https://uqworld.org/t/copula-not-working-with-inverse-analysis/1905)
**Author:** [@Truong\_Le](https://uqworld.org/u/Truong_Le)\ **Replies:** 1\ **Last updated:** [June 1, 2023, 5:26pm UTC](https://uqworld.org/t/copula-not-working-with-inverse-analysis/1905 "2023-06-01T17:26:44Z")
Hi, I’ve run into a problem when trying to feed an input function with a copula into an inverse analysis. I have modified the “INVERSION: SIMPLE BEAM CALIBRATION” file. %% INVERSION: SIMPLE BEAM CALIBRATION % % In th… --- ## [Can I view or access the mathematical formula or programming source code for the algorithm?](https://uqworld.org/t/can-i-view-or-access-the-mathematical-formula-or-programming-source-code-for-the-algorithm/1897)
**Author:** [@yl\_z](https://uqworld.org/u/yl_z)\ **Replies:** 0\ **Last updated:** [May 23, 2023, 11:13am UTC](https://uqworld.org/t/can-i-view-or-access-the-mathematical-formula-or-programming-source-code-for-the-algorithm/1897 "2023-05-23T11:13:18Z")
Hello, community friends, it is a great honor to use UQlab such a convenient and easy to use tool. UQlab’s algorithm follows the black box method, which means that these algorithms are encapsulated in the software, as a … --- ## [Maximum-interaction-adaptive option in PCE?](https://uqworld.org/t/maximum-interaction-adaptive-option-in-pce/1890)
**Author:** [@Ahmadnr](https://uqworld.org/u/Ahmadnr)\ **Replies:** 0\ **Last updated:** [May 15, 2023, 10:18am UTC](https://uqworld.org/t/maximum-interaction-adaptive-option-in-pce/1890 "2023-05-15T10:18:30Z")
Dear UQLab, I am trying to build a PCE-based metamodel using degree-adaptive and q-norm-adaptive options. I was wondering if there is also any adaptive option for maximum interaction hyperparameter (r)? If not, do I nee… --- ## [UQLink : Abaqus outputs two result files, How can I read the results from both files separately?](https://uqworld.org/t/uqlink-abaqus-outputs-two-result-files-how-can-i-read-the-results-from-both-files-separately/1883)
**Author:** [@Mr121Tony](https://uqworld.org/u/Mr121Tony)\ **Replies:** 6\ **Last updated:** [May 9, 2023, 9:19am UTC](https://uqworld.org/t/uqlink-abaqus-outputs-two-result-files-how-can-i-read-the-results-from-both-files-separately/1883 "2023-05-09T09:19:53Z")
Dear Professor, How do I modify the readabaqusOutput.m file when my abaqus software outputs two result files and I need to read the results from both files separately? best wishes! Tony Smith --- ## [RBDO: Is it possible to optimize a discrete parameter?](https://uqworld.org/t/rbdo-is-it-possible-to-optimize-a-discrete-parameter/1852)
**Author:** [@Eduardo\_Paula](https://uqworld.org/u/Eduardo_Paula)\ **Replies:** 2\ **Last updated:** [May 8, 2023, 6:37pm UTC](https://uqworld.org/t/rbdo-is-it-possible-to-optimize-a-discrete-parameter/1852 "2023-05-08T18:37:50Z")
Hello. First of all, I would like to thank your team for developing the excellent UQLab framework. I’m developing a model in which I intend to optimize a component whose cost function is defined by the product between … --- ## [How to find the number of function evaluations (g-calls) in the RBDO module](https://uqworld.org/t/how-to-find-the-number-of-function-evaluations-g-calls-in-the-rbdo-module/1830)
**Author:** [@ali](https://uqworld.org/u/ali)\ **Replies:** 5\ **Last updated:** [May 8, 2023, 11:54am UTC](https://uqworld.org/t/how-to-find-the-number-of-function-evaluations-g-calls-in-the-rbdo-module/1830 "2023-05-08T11:54:22Z")
Dear UQLab, Thanks again for the amazing RBDO module. I am a little bit confused about finding the number of function evaluations (g-calls) in a surrogate-assisted RBDO problem. In other words, if we have a model named… --- ## [Combination of inferred probabilistic models](https://uqworld.org/t/combination-of-inferred-probabilistic-models/1874)
**Author:** [@HZhang](https://uqworld.org/u/HZhang)\ **Replies:** 2\ **Last updated:** [May 4, 2023, 8:21pm UTC](https://uqworld.org/t/combination-of-inferred-probabilistic-models/1874 "2023-05-04T20:21:04Z")
Hi everyone, I am currently working on a numerical model that involves four inputs, namely x1, x2, x3, and x4. My first task is to create a probabilistic model for the inputs using the inference conducted with the obser… [Previous page](https://uqworld.org/c/uq-with-uqlab/community-q-a-howto/11.md?page=2) [Next page](https://uqworld.org/c/uq-with-uqlab/community-q-a-howto/11.md?page=4)