# Update design parameter in TO
**URL:** https://discourse.julialang.org/t/update-design-parameter-in-to/99242
**Category:** New to Julia
**Tags:** question, package, diffeq
**Created:** [May 22, 2023, 6:28pm UTC](https://discourse.julialang.org/t/update-design-parameter-in-to/99242 "2023-05-22T18:28:38Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@mary](https://discourse.julialang.org/u/mary)
#### Post date: [May 22, 2023, 6:28pm UTC](https://discourse.julialang.org/t/update-design-parameter-in-to/99242/1 "2023-05-22T18:28:38Z")
Hi. in tutorial 18 of gridap I couldn’t understand how gridap update design density. because i have done similar but it always gives me zero and says that the matrix A is singular. can anyone explain me about the procedure? thank you
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### Author:  [@nilshg](https://discourse.julialang.org/u/nilshg)
#### Post date: [May 23, 2023, 7:40am UTC](https://discourse.julialang.org/t/update-design-parameter-in-to/99242/2 "2023-05-23T07:40:37Z")
Please read
> [@Please read: make it easier to help you](https://discourse.julialang.org/t/please-read-make-it-easier-to-help-you/14757):
>
> Welcome to the Julia Discourse! We are enthusiastic about helping Julia programmers, both beginner and experienced. This public service announcement (PSA) outlines best practices when asking for help. Following these points makes it easier for us to help you and more likely you’ll get a prompt, useful answer. Keywords are highlighted to make it easier to refer to specific points. Choose a descriptive title that captures the key part of your question, eg “plots with multiple axes” instead of …
and amend your question accordingly. In this case this would likely mean linking to the tutorial in question and ideally copying out the bits that aren’t working for you in a way that others can run it on their machines (i.e. including importing relevant packages and defining all variables used).