# Linked Questions

4answers
668 views

### NDSolve DAE with Constraints

I'm trying to make some numerical simulation with NDSolve. I have encountered a few problems. Here is a simplified version of the equations: ...
2answers
276 views

### Underflow error General::munfl from E^x instead of Exp[x]

In contrast to earlier versions, Mathematica 11.3 and 12.0 generate lots of underflow errors from my code, e.g. ...
3answers
3k views

### Machine precision near zero: not fulfilled?

I am puzzled by the behavior of Mathematica machine precision with numbers approaching zero. This manifests itself, e.g., with FixedPoint and the like. In the ...
4answers
713 views

### SetOptions locally?

Is there a way to SetOptions locally? For example, I have a Module and inside it I am doing a lot of ...
1answer
544 views

### DSolve with SetOptions[Solve, Method -> Reduce] Behaving Differently in Ver 11.1.1

With version "11.1.1 for Microsoft Windows (64-bit) (April 18, 2017)", DSolve[{SI'[s] == Sin[PH[s]] , PH'[s] == Sin[SI[s]]/e}, {SI[s], PH[s]}, s] produces the ...
8answers
827 views

### Product of elements of a list

Sum is for functions; Total is for a list. Product is for a function; what is the command ...
1answer
700 views

### Why does 1 - Exp[-10.0^12] cause an out-of-memory error?

I would like to understand why evaluation of the expression 1 - Exp[-10.0^12] causes an out-of-memory error and how can I prevent such errors when calculating ...
3answers
578 views

### Why does DSolve return two solutions for my ODE?

I wanted to solve the differential equation: $y’ = (1+2x)\sqrt{y}$ with $y(0) = 1$. It can be done by hand, and to check my answer I typed the following in Mathematica ...
2answers
231 views

### Change lighting in ChromaticityPlot3D

It looks to me like ChromaticityPlot3D has some default lighting, but unlike most Graphics3D functions the Lighting option doesn't seem to have any effect. However, the documentation states "...
1answer
175 views

### Change system options in package

I use Mathematica mostly for numerical calculations, and sometimes the performance of numerical calculations can be greatly improved if the high-precision arithmetic can be switched off by ...
2answers
281 views

### CompiledFunction returns machine numbers smaller than $MinMachineNumber When thinking on the workaround for this LogLogPlot bug suggested by halirutan I noticed that CompiledFunction actually can ... 0answers 101 views ### Calculating eigensystem of a matrix containing very small numbers [duplicate] I'm dealing with a matrix containing very small numbers like 10^(-370). When I compute the eigensystem of my matrix, it takes too much time, though the matrix size is not large. Can anyone explain ... 1answer 294 views ### Slow exponential evaluation over lists This question,which is still unanswered, might be relevant because it involves NIntegrate over lists and it also has Exp. In ... 0answers 131 views ### Can I force Mathematica to use machine precision? [duplicate] Some built-in functions (like Exp) give an arbitrary precision result, even when the argument is a machine precision number. Example: ... 2answers 310 views ### Optimizing code containing an infinite sum I have the following expression. It's based on the negative-log-likelihood of a Poisson-Gaussian noise model, i.e. a convolution of a Poisson & Normal distribution. The value$x_{i}\$ is the ...

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