4
votes
Solving system of first order PDEs
Update: Solution accuracy modestly improved and accuracy estimate appended.
The Finite Element Method used in the last section of the question approximates the PDEs by thousands of sparsely coupled ...
4
votes
Accepted
How to solve this integral equation numerically?
Although the general problem in the question probably requires the methods referenced by flinty in 285076, the specific problem contained in the question's code, ...
4
votes
Accepted
4
votes
Accepted
3
votes
Multiple solutions from NSolve
For parametric research it could be better to use FindRoot as follows
...
3
votes
Modeling experimental data with differential equations
This should help you underway, but I couldn't find good starting values for the parameters:
...
2
votes
Accepted
Plotting an integral with solving for a specific constant
As an example, we take a simple function that we can integrate analytically:
f[t_] = t + 2;
Integrate analytically:
...
1
vote
Accepted
Using ParametricNDSolveValue and MultiNonlinearModelFit to fit an ODE system to datasets
I split the data values and uncertanties into two separate lists, and also grab the time values:
...
1
vote
Multiple solutions from NSolve
With the OP's sol, we can gather the similar solutions together, find their mean, and if desired, polish them up with FindRoot:
<...
1
vote
Multiple solutions from NSolve
Setting WorkingPrecision->20, it then takes 85 sec. and gives only 3 solutions, although it gives a warning that the input is less precise than working precision:
...
1
vote
Plot after applying NIntegrate
int is producing seemingly random numbers because AccuracyGoal -> 5, PrecisionGoal -> 4 are too small. Increasing the ...
1
vote
Accepted
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