User Portlet
| Discussions |
|---|
| On 25 March 2021, David Park gave the 51-minute talk *Introductory Tour of Grassmann Algebra and Calculus in Mathematica* ( https://www.youtube.com/watch?v=TGGDihbLm6g ). The application is a joint advanced developmental project by David Park and... |
| In WL 12.2, AxiomaticTheory@"RingAxioms" returns 1-sided distributivity. But 2-sided distributivity characterizes a ring. Why does RingAxioms behave this way? It seems that a new theory (say NearRingAxioms) could treat 1-sided... |
| Each X-element below is a pair that has a label and xy-point. How do I cluster the X-elements using the distance between points? The code below balks because the data structure is incompatible with FindClusters. If X had points only then... |
| From a univariate polynomial, I want to delete nonconstant terms whose exponents are less than a threshold. The line below works as planned: In[34]:= 2 + 3 x - x^2 + 5 x^3 + 9 x^8 /. {(x^k_ /; k 0, Times[ _, x] -> 0} Out[34]= 2 +... |
| What's the easy way to display a multilinear equation as sorted on its coefficients? For instance, display 7 + 3x[1] - 2x[2] + x[3] as 7 - 2x[2] + x[3] + 3x[1] I'm now converting the equation into a list of {coefficient,... |
| Why does the code below yield the positions given? In particular, why do {1,0}, {2,0} appear when these positions are not at level 2? When UnsameQ is replaced by x neq infinity I get the correct result. Thanks. Position[({ {?,... |
| The mean and variance of a Kumaraswamy distribution with parameters a = 2 and b = 3 are respectively 16/35 and 201/4900. When I solve the 2x2 system below for parameters a and b, Mathematica gags (likewise with NSolve and Reduce). FindRoot works,... |
| Re Mathematica 10.3 under Windows 7. From the list {1,2,3,4,5} I want to zero in on 1 and 3 and return the list of their squares, i.e., {1,9}. This is easy enough to do using Cases[Range@5,1|3]^2. Noting that this example is a... |
| Re Mathematica 10.3 under Windows 8. I use GeoListPlot to show Italy. To mark Rome, I use Labeled[..., Style["Rome",12,Blue]] -- this puts the label "Rome" to the upper-right of the marker. How do I reposition the label to the lower-left and... |
| Re Mathematica 10.2 running under Windows 8. This compiled code adds the integers between 1 and n! inclusive. Yes, it's easier to use the formula n! (n! + 1) / 2 but I'm timing a loop. g = Compile[{{n, _Integer}}, Module[{s = 0}, Do[s += k,... |