Tag Info

How to use Mathematica in AWS cloud?

Install version 11.3 of the player, write your script.wl and run wolframscript -f script.wl If you want a GUI check https://...
• 2,060

Finding the frequency of letters in a string

Why not use LetterCounts LetterCounts[sentence, IgnoreCase -> True] // KeySort N[#]/Total[#] &[%] ...
• 9,863

Build API without the WolframCloud?

Currently APIFunction / CloudDeploy works only with the Public Cloud or an Enterprise Private Cloud. So either you need an EPC ...

Graph databases / Nosql with Mathematica

Wolfram Language version 11.3 now has support for interfacing with MongoDB. You can connect to a MongoDB database via MongoConnect. For example, connecting to a ...
• 3,479

How to put a loop in a loop

Define random using SetDelayed so that each time it is used it gives a different random vector: ...
• 399k
Accepted

Jacobian matrix evaluation at a point

Let f be a vector function: f[x_, y_] := {f1[x, y], f2[x, y]}; Then the Jacobian is the matrix valued function: D[f[x, y], {{x, y}}] and the Jacobian at point {a,b} is: ...
• 53.6k
Accepted

How to make a matrix that had diffrentation without functions

One possiblity is to define the function d as: d = {{D[#, x], 0}, {0, D[#, y]}, {D[#, x], D[#, y]}} & To apply this operator to a particular function: ...
• 69.4k

webmathematica to share my game?

This applies to any Wolfram Cloud based web application, not simply to your question, but there are say 4 steps involved in creating a web app. Hopefully some of this carries over from WC to ...
• 47k

Jacobian matrix evaluation at a point

You can do it as follows: Vector field: F[{x_, y_}] := Evaluate[{f1[x, y], f2[x, y]}] X = {x, y}; X0 = {a, b}; The Jacobian Matrix: ...
• 27.7k

How do I create cobweb iterations or stair steps **WITH ARROWS** to show attractive and repulsive fixed points for a graph?

If we have two functions that we're "bouncing" between, then at each step we can solve for how to move horizontally or vertically from one function to the other. We need to know whether for ...
• 30.4k

Finding the frequency of letters in a string

Use LetterCounts as in Αλέξανδρος Ζεγγ's answer: lc = KeySort @ LetterCounts[sentence, IgnoreCase -> True] To get the ...
• 399k

Build API without the WolframCloud?

Now there's WolframWebEngine which allows one to create a sort of personal wolfram cloud.
• 2,060

Jacobian matrix evaluation at a point

If you have a look at this link you can take the code as appears there. Namely, ...
• 16.4k

I need help in complements of subsets

You have too many braces in TTt. Note also, you should not use uppercase names, because these are used by the system. Here is working code: ...
• 53.6k

I need help in complements of subsets

We could also use DeleteElements (new in 13.1) a = {{P1}, {P2, P3}}; b = {P1, P2, P3, P4}; DeleteElements[b, #] & /@ a {P2,...
• 81.3k

How to calculate this limit？

As simple as using Limit: Clear[n]; Limit[n^2 ((1 + 1/(1 + n))^(n + 1) - (1 + 1/n)^n), n -> ∞] (*E/2*)
• 1,534

...
• 25.6k

How do I create cobweb iterations or stair steps **WITH ARROWS** to show attractive and repulsive fixed points for a graph?

Clear["Global`*"] Without the arrows just use ResourceFunction["CobwebPlot"] ...
• 160k
Accepted

How to display a True/False table

One could use a mixture of Table, Cases and If to produce the desired result. Here are the ...
• 14.5k

Plotting a few Maclaurin Series in Mathematica

Here's one way: Plot[ Evaluate@Normal@Series[{Exp[Sin[x]], (x^2 + Exp[x])^(-1), Exp[-4 x^2 + 5 x]}, {x, 0, 5}], {x, -1/2, 1/2}]
• 239k

Use FIT to calculate regression line from two sets of data

The way the question is phrased you have two lists that need to be joined and then apply a linear fit to the joined list. To join them use: ...
• 14.5k

Finding the frequency of letters in a string

Does this not accomplish what you're after? Reverse[SortBy[ Tally[ToLowerCase@ StringCases[sentence, LetterCharacter]], #[[2]] &]]
• 4,292
Accepted

Plot streamplot for two stability point for Jacobian

Without your function we can't give a full answer, but this should suffice: ...
• 41.8k
Accepted

Graphing and calculating the volume using mathematica (or other)

A possible general approach (not fully verified or optimized). The strategy is as follow: Position the solid and cutting cylinders (also solid in my case). Move the cutting cylinder along its axis ...
• 5,222
1 vote

How can I plot a hexagon inside this cylinder so that it is always in the same direction as the cylinder, no matter what the orientation is?

You can use the Method option to get an n-gonal prism inscribed in a clylinder in two ways: Use the Method suboption ...
• 399k
1 vote

...
• 77.8k
1 vote

code in mathematica for the game of guessing

Here you have a minimal solution to get you started. ...
• 8,478
1 vote

Manipulating the plots obtained from NDSolve

It is bad practice and dangerous to use the same symbol name in the ODE and for the solution function. Anyway, with the code below you can play with your parameters. ...
• 53.6k
1 vote