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by Paul
February 13th, 2020, 4:30 pm
Forum: Numerical Methods Forum
Topic: About solving a transport equation
Replies: 151
Views: 52770

Re: About solving a transport equation

I don't have any fresh viewpoints! I'm just regurgitating some basic things I learned 40 years ago!
by Paul
February 13th, 2020, 4:19 pm
Forum: Off Topic
Topic: How good or bad are the pandemic warning models?
Replies: 288
Views: 55778

Re: How good or bad are the pandemic warning models?

These models tend to have similar shapes. S shaped for total number of deaths, i.e. a peak in death rate. But which is the right model since they all look the same? Until yesterday I had an incredible fit for a simple model based on tw's " I wonder if  one can solve the basic model with simple time-...
by Paul
February 13th, 2020, 5:48 am
Forum: Student Forum
Topic: Silly questions
Replies: 94
Views: 14846

Re: Silly questions

Well, if we are going to be so literal, then since the original post did not want an answer but a vote I am going to vote yes!! This is maths 21st century style!
by Paul
February 13th, 2020, 2:04 am
Forum: Student Forum
Topic: Silly questions
Replies: 94
Views: 14846

Re: Silly questions

But we do now know that the answer to Cuch's question is no!
by Paul
February 13th, 2020, 2:03 am
Forum: Student Forum
Topic: Silly questions
Replies: 94
Views: 14846

Re: Silly questions

The named function just happens to be the answer!

Exam question 1: Find the solution of ...

Answer: Define [$]\mbox{Lewis}_1[$] as the answer to question 1. Trivially and wlog the answer to question 1 is [$]\mbox{Lewis}_1[$].

Exam question 2: Etc.

!!!
by Paul
February 13th, 2020, 1:28 am
Forum: Student Forum
Topic: Silly questions
Replies: 94
Views: 14846

Re: Silly questions

That looks a bit circular to me!
by Paul
February 12th, 2020, 11:36 pm
Forum: Off Topic
Topic: How good or bad are the pandemic warning models?
Replies: 288
Views: 55778

Re: How good or bad are the pandemic warning models?

Spot which of the below are not seeking more funding:  I hope this outbreak may be over in something like April Prof. Nanshan Zhong Leading epidemiologist, first to describe SARS coronovirus Feb. 11, 2020  It could infect 60% of global population if unchecked Prof. Gabriel Leung Expert on coronaviru...
by Paul
February 12th, 2020, 11:25 pm
Forum: Off Topic
Topic: How good or bad are the pandemic warning models?
Replies: 288
Views: 55778

Re: How good or bad are the pandemic warning models?

The Dalai Lama has cancelled events in response to Covid19. 

Is this peak hysteria? If it is then that probably coincides with peak death rate.
by Paul
February 12th, 2020, 10:38 pm
Forum: Student Forum
Topic: Silly questions
Replies: 94
Views: 14846

Re: Silly questions

Via gamma fn, looks messy!
by Paul
February 12th, 2020, 7:12 pm
Forum: Off Topic
Topic: How good or bad are the pandemic warning models?
Replies: 288
Views: 55778

Re: How good or bad are the pandemic warning models?

It's a simple change of parameter!
by Paul
February 12th, 2020, 6:13 pm
Forum: Numerical Methods Forum
Topic: About solving a transport equation
Replies: 151
Views: 52770

Re: About solving a transport equation

1) You like transforming coords. So change to coords that move with the chars.

Or

2) Constrain dy and dt so that you solve numerically along the chars. That’s what I’ve used in the past.
by Paul
February 12th, 2020, 4:19 pm
Forum: Politics Forum
Topic: Time for BREXIT FAQ
Replies: 195
Views: 23119

Re: Time for BREXIT FAQ

Yet, the British — whose “The Office” and Monty Python shows have become pillars of English-language humor — learn from the Badoo poll that they are not as funny as they think. They placed just seventh out of 15 — behind the Brazilians, French and Mexicans. 
Good one! Made me chuckle!
by Paul
February 12th, 2020, 4:11 pm
Forum: Off Topic
Topic: How good or bad are the pandemic warning models?
Replies: 288
Views: 55778

Re: How good or bad are the pandemic warning models?

This should never have been a Springer book. Springer books are awful. Their only redeeming feature is that being yellow you can see them from a long way away. My old edition of JM's book is a nice green though. Before getting into time dependence I would recommend doing a nondimensionalization. Jus...
by Paul
February 12th, 2020, 1:30 am
Forum: Politics Forum
Topic: Time for BREXIT FAQ
Replies: 195
Views: 23119

Re: Time for BREXIT FAQ

This is going to be controversial, but Arnie is a girly man then!
by Paul
February 12th, 2020, 1:29 am
Forum: Off Topic
Topic: How good or bad are the pandemic warning models?
Replies: 288
Views: 55778

Re: How good or bad are the pandemic warning models?

In SIR the Rs are both dead and recovered+immune I.e. can’t cause any more infections. In going from R to number dead is the easy bit! You need SIR plus a transition matrix for travel between airports plus diffusion in space. It’s just a credit risk model! Corid19 low mortality but long quarantine B...
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