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http://community.wolfram.com/groups/-/m/t/1531128
Hey this classes homework started out at a little bit of a challenge but now I actually have no idea how to do the following. If anyone could help it would be greatly appreciated.
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[1]: http://community.wolfram.com//c/portal/getImageAttachment?filename=IMG_9765.JPG&userId=1530794
[2]: http://community.wolfram.com//c/portal/getImageAttachment?filename=IMG_9766.JPG&userId=1530794Trevor Naport2018-10-23T22:01:37ZInterpolationOrder->2 splits up the graph
http://community.wolfram.com/groups/-/m/t/1530494
Hello I use `ListLinePlot function and interpolationorder ->2
When it's 1 it dosent splits up the graph into two part. When it's 2 and more it does. So my question is how to make it connected? ![enter image description here][1]
[1]: http://community.wolfram.com//c/portal/getImageAttachment?filename=1.jpg&userId=1358636Alex Graham2018-10-23T15:40:59ZHow WolframLibraryData::Message gets the library name
http://community.wolfram.com/groups/-/m/t/1525995
I was following the [LibraryLink documentation][1]. There are two ways to send an error from inside the C library. one using `WolframLibraryData::Message` which takes `"tag"` as an input. The second way is to send the following expression over `MLink`.
Message[MessageName[MyFunction, "tag"], e1, e2, ...]
Now This `MyFunction` is the Mathematica name assigned for the Library possibly with `LibraryFunctionLoad`.
MyFunction = LibraryFunctionLoad[lib,fun, ...]
The library `lib` is apparently unaware about the user given name `MyFunction`.
So how will the library use the name `MyFunction` while constructing the `MessageName` expression ?
On the other hand the `WolframLibraryData::Message` function does not require the function name to be passed. It some how magically figures this out. Although it has it's own problem (Inability of passing parameters to the error messages).
There are two possibilities.
1. the user given name is supplied to the library through some hidden attribute in the LibraryData.
2. There is a special symbol like `$CurrentLibraryFunction` that can be used as a placeholder for `MyFunction` which will be resolved latter.
Are any of these two possibilities true ? Is there any hackish way to know the name of the Library Function ?
[1]: https://reference.wolfram.com/language/LibraryLink/tutorial/LibraryStructure.html#59563264Neel Basu2018-10-21T19:49:06ZMATH-TWS: Connecting Mathematica to Interactive Brokers TWS
http://community.wolfram.com/groups/-/m/t/1527021
MATH-TWS is a new Mathematica package that connects Wolfram Mathematica to the Interactive Brokers TWS platform via the C++ API. It enables the user to retrieve information from TWS on accounts, portfolios and positions, as well as historical and real-time market data. MATH-TWS also enables the user to place and amend orders and obtain execution confirmations from Mathematica.
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I have wanted a way to connect Wolfram Mathematica to Interactive Brokers’ Trader Workstation for the longest time. Now that it is finally available with MATH-TWS I am excited by the possibilities for Mathematica users.
The first release of MATH-TWS will be available within a couple of weeks. Anyone interested in licensing a copy should email algorithmicexecution@gmail.com with MATH-TWS in the subject line.
[1]: http://community.wolfram.com//c/portal/getImageAttachment?filename=twsConnect.png&userId=773999
[2]: http://community.wolfram.com//c/portal/getImageAttachment?filename=twsAccounts.png&userId=773999
[3]: http://community.wolfram.com//c/portal/getImageAttachment?filename=twsAccounts2.png&userId=773999
[4]: http://community.wolfram.com//c/portal/getImageAttachment?filename=twsAccounts3.png&userId=773999
[5]: http://community.wolfram.com//c/portal/getImageAttachment?filename=HistoricalData.png&userId=773999
[6]: http://community.wolfram.com//c/portal/getImageAttachment?filename=DataManipulation.png&userId=773999
[7]: http://community.wolfram.com//c/portal/getImageAttachment?filename=TimeSeries.png&userId=773999
[8]: http://community.wolfram.com//c/portal/getImageAttachment?filename=IntradayData.png&userId=773999
[9]: http://community.wolfram.com//c/portal/getImageAttachment?filename=Currentmarketdata.png&userId=773999
[10]: http://community.wolfram.com//c/portal/getImageAttachment?filename=News.png&userId=773999
[11]: http://community.wolfram.com//c/portal/getImageAttachment?filename=Ordermanagement.png&userId=773999
[12]: http://community.wolfram.com//c/portal/getImageAttachment?filename=Modifyorder.png&userId=773999
[13]: http://community.wolfram.com//c/portal/getImageAttachment?filename=Cancelorder.png&userId=773999Jonathan Kinlay2018-10-22T12:09:47ZView all calculation steps used by Inverse[] on a matrix?
http://community.wolfram.com/groups/-/m/t/1525459
I want to view all the calculation steps performed by Wolfram to arrive at the resultant matrix for the below:
MatrixForm[
Inverse[{{20, 13, 8}, {0, 14, 18}, {8, 0, 0}},
Modulus -> 29]]
Is there a code that will allow me to see all these calculation steps in either Wolfram Alpha or Mathematica?Curtis Poyton2018-10-21T12:00:06ZConvert a Wolfram Language code into a Matlab code?
http://community.wolfram.com/groups/-/m/t/1524803
I wrote a Mathematica code for image encryption , but unfortunately , I do not know a code to test the security level achieved with my code in Mathematica. But I found a code in Matlab for testing the security level of my code. Now I want to take the result encrypted image from Mathematica code and test its security level by Matlab. Or convert Mathematica code into Matlab code.
Can anyone help me please?Roayat Ismail2018-10-21T01:05:35ZHas the behavior of $RecursionLimit changed?
http://community.wolfram.com/groups/-/m/t/1523515
The tutorial [Controlling Infinite Evaluation][1] says:
> When the Wolfram Language stops without finishing evaluation, it returns a held result. You can continue the evaluation by explicitly calling `ReleaseHold`.
It includes this minimal example:
> `In[1]:= x = x + 1`
>
> ... $RecursionLimit: Recursion depth of 256 exceeded.
>
> `Out[2]= 255 + Hold[1 + x]`
It appears this is no longer the behavior in version 11.3. Instead of evaluating to a partial result when `$RecursionLimit` is reached, the *original* expression wrapped in `Hold` is returned. Actually, to be more precise, when I evaluate `x=x+1` on a fresh kernel I get `Hold[x+1]`, but if I set `$RecursionLimit` to any valid number I get `Hold[x=x+1]`.
In contrast, the behavior of `$IterationLimit` is as documented.
The Mathematica StackExchange discussion for reference: https://mathematica.stackexchange.com/questions/184259/unwanted-hold-from-recursive-function/
[1]: https://reference.wolfram.com/language/tutorial/ControllingInfiniteEvaluation.htmlRobert Jacobson2018-10-20T04:43:11ZGet LibraryLink function name from inside the library?
http://community.wolfram.com/groups/-/m/t/1523963
When developing with LibraryLink, is there any way to get the function name from inside the library ?
I don't think there is a way to find out the name of the function that have been used to access the C function like the `FunctionX` shown in the example bellow.
FunctionX = LibraryFunctionLoad[...]
I suspect there might be something in `WolframRuntimeData` but this one is not documented anywhere.Neel Basu2018-10-20T17:04:14ZI2C connected to WM Raspberry to / from WM Desktop help
http://community.wolfram.com/groups/-/m/t/1522036
I am intested to connect, capture and process an Image from a sensor with a I2C protocol . I know that the RaspberryPi WM may connect to the device, but the small Raspberry device does not have the computational power to process the video delivered by the image sensor device.
It it possible that my p W Mathematica desktop command the I2C image sensor and draw the image for processing from the desktop mathematica?Jose Calderon2018-10-19T11:42:07ZThe Octagonal Dodecahedron
http://community.wolfram.com/groups/-/m/t/1520664
On 17 October 2018, [Ivan Neretin discovered the octagonal dodecahedron](https://math.stackexchange.com/questions/2869725/), a toroid made from twelve octagons.
**4**, 6, 8 triangles can make a tetrahedron and up. The [Snub Disphenoid](http://mathworld.wolfram.com/SnubDisphenoid.html) has 12 faces.
**6**, 8, [9](https://en.wikipedia.org/wiki/Herschel_graph), 10 quadrilaterals can make a cube and up. The [Rhombic Dodecahedron](http://mathworld.wolfram.com/RhombicDodecahedron.html) has 12 faces.
**12**, 16, 18, 20 pentagons can make a [tetartoid](http://demonstrations.wolfram.com/TheTetartoid/) or dodecahedron [and up](https://math.stackexchange.com/questions/1609854/).
**7**, 8, 9, 10 hexagons can make make a [Szilassi toroid](http://demonstrations.wolfram.com/TheParametrizedSzilassiPolyhedron/) and [up](http://dmccooey.com/polyhedra/ToroidalRegularHexagonal.html).
**12**, 24 heptagons can make a [heptagonal dodecahedron](http://dmccooey.com/polyhedra/HigherGenus.html) or [Klein quartic 3-torus](http://mathworld.wolfram.com/KleinQuartic.html).
**12** octagons can make an octagonal dodecahedron.
![octagonal dodecahedron][1]
So how did I make that picture? First, I looked through the [Canonical Polyhedra](https://datarepository.wolframcloud.com/resources/Canonical-Polyhedra) resource object for the outer polyhedron. The index turned out to be "8_9".
ResourceObject["Canonical Polyhedra"]
ResourceData["Canonical Polyhedra"][["8_9"]]
It's a geometric object with constraints since it's a [canonical polyhedron](http://demonstrations.wolfram.com/CanonicalPolyhedra/). My WTC talk [Narayama's Cow and Other Algebraic Numbers](https://wtc18.pathable.com/meetings/895905) discussed how to use algebraic number fields to simplify geometrically constrained objects.
1. Get two or more points to simple fixed values.
2. Use RootApproximant[] on remaining points.
3. If remaining points have the same value for NumberFieldDiscriminant[coord^2], the object is in an algebraic number field.
Would the technique I suggested help to make the new object? Turns out it did.
I took the points from "8_9", kept the center at (0,0,0), found an EulerMatrix[] to forced the midpoints of two opposing edges to (0,0,1),(0,0,-1) and force those two edges to be parallel to the x,-y axes.
After using Chop[] in various ways to get 0, 1, and -1 values, I used RootApproximant[] on everything else, then looked at NumberFieldDiscriminant[coord^2] on all reasonable seeming values. The discriminant -104 turned out a lot, and soon I had all coordinates using the algebraic number field based on Root[#^3 - # - 2 &, 1].
I've found these functions useful for algebraic number fields.
FromSqrtSpace[root_, coord_] := Module[{ dim, degree, vector},
dim = Dimensions[coord];
degree = {1, 2}.NumberFieldSignature[root];
vector = (root^Range[0, degree - 1]);
Map[With[{k = (#).vector}, RootReduce[Sign[k] Sqrt[Abs[k]]]] &, coord, {Length[dim] - 1}]];
ToSqrtSpace[root_, coord_] := Module[{dim, order, algebraic},
dim = Dimensions[coord];
order = {1, 2}.NumberFieldSignature[root];
algebraic = Map[Function[x, ToNumberField[Sign[x] RootReduce[x^2], root]], coord,{Length[dim] - 1} ];
Map[Function[x, If[Head[x] === AlgebraicNumber, Last[x], PadRight[{x}, order]]], algebraic, {Length[dim]} ]];
The algebraic number field coordinates, actual coordinates, and faces.
valsV={{{0,1/2,-1/4},{0,0,0},{-1,0,0}},{{-2,0,1},{0,-2,1},{-1,2,-1}},{{0,2,-1},{2,0,-1},{1,-2,1}},{{0,2,-1},{-2,0,1},{1,-2,1}},{{-2,0,1},{0,2,-1},{-1,2,-1}},{{0,-1/2,1/4},{0,0,0},{-1,0,0}},{{0,0,0},{0,1/2,-1/4},{1,0,0}},{{0,0,0},{0,-1/2,1/4},{1,0,0}},{{2,0,-1},{0,2,-1},{-1,2,-1}},{{2,0,-1},{0,-2,1},{-1,2,-1}},{{0,-2,1},{-2,0,1},{1,-2,1}},{{0,-2,1},{2,0,-1},{1,-2,1}}};
p89v = FromSqrtSpace[Root[#^3 - # - 2 &, 1], valsV];
p89F={{1,2,3,4,5},{2,10,12,8,3},{4,7,11,9,5},{6,9,11,12,10},{1,5,9,6},{1,6,10,2},{3,8,7,4},{7,8,12,11}};
Code for the initial picture.
reg=RegionBoundary[RegionDifference[ConvexHullMesh[p89v],ConvexHullMesh[With[{a=.7, b=.6, c=.9},{{a,b,c}, {-a,-b,c},{-b,a,-c}, {b,-a,-c} }]]]];
DiscretizeRegion[reg,MeshCellStyle->{{2,All}->Opacity[.7]}, SphericalRegion-> True, ImageSize-> 600, ViewAngle-> Pi/10]
Showing the original polyhedron and subtracted tetrahedron.
Graphics3D[{EdgeForm[Thick], Opacity[.8], GraphicsComplex[p89v, Polygon[p89F]],
With[{a = .7, b = .6, c = .9}, Polygon[Subsets[{{a, b, c}, {-a, -b, c}, {-b, a, -c}, {b, -a, -c} }, {3}]]]}, Boxed -> False, SphericalRegion -> True, ViewAngle -> Pi/9]
![octagonal dodecahedron][2]
Might be possible to remove the canonical sub-polyhedron constraint and add a constraint that the octagons all have unit area. Or to minimize the ratio of largest/smallest edge.
If you'd like a hexagonal dodecahedron, here's a simple one.
DiscretizeRegion[RegionBoundary[RegionDifference[Region[Cuboid[{0, 0, 0}, {3, 3, 3}]],
RegionUnion[Region[Cuboid[{0, 0, 0}, {2, 2, 2}]], Region[Cuboid[{1, 1, 1}, {3, 3, 3}]]]]],
MaxCellMeasure -> {"Area" -> 0.001}, AccuracyGoal -> 8, PrecisionGoal -> 8]
![hexagonal dodecahedron][3]
[1]: http://community.wolfram.com//c/portal/getImageAttachment?filename=octagonaldodecahedron.jpg&userId=21530
[2]: http://community.wolfram.com//c/portal/getImageAttachment?filename=octagonaldodecbuild.jpg&userId=21530
[3]: http://community.wolfram.com//c/portal/getImageAttachment?filename=hexagonaldodecahedron.jpg&userId=21530Ed Pegg2018-10-18T21:43:37ZMathematica no longer available for the Raspberry Pi?
http://community.wolfram.com/groups/-/m/t/1511397
EDIT 2: As noted below, the problem is now resolved.
----
EDIT and warning: If you have Mathematica on the Raspberry Pi right now, do not uninstall at this point.
----
Mathematica is no longer included in the Raspbian repositories or the default Raspbian image. The Mathematica and Wolfram Language sections of the Raspberry Pi forum have been purged—apparently gone for good.
I uninstalled it, planning to reinstall a newer version, and it seems that now I lost it permanently.
Are there plans to make it available again?
There's also [a thread about this on the Raspberry Pi forums](https://www.raspberrypi.org/forums/viewtopic.php?t=224629). People speculate that Wolfram no longer licenses Mathematica for Raspbian, which seems strange/doubtful to me given that [11.3 for the RPi was released just 3 months ago](http://community.wolfram.com/groups/-/m/t/1349489), i.e. development seems to be ongoing.
Can anyone from Wolfram comment please?Szabolcs Horvát2018-10-14T14:56:10ZWhat is the default precision of ` when not specifying a digit after it?
http://community.wolfram.com/groups/-/m/t/1518918
If the symbol ` has no digits after it, what is the precision of the number understood to be?
Here is a the sample code:
DKReplace = {70.6`, 74.2`, 80.1`, 75.3`, 55.6`, 55.5`, 62.6`, 64.9`,
80.1`, 102.5`};
Thank you,
BenoitBenoit Cordoba2018-10-17T23:43:08ZWhich version of Mathematica is available on Raspberry Pi ?
http://community.wolfram.com/groups/-/m/t/1349489
Hello,
I recently added Mathematica on my Raspberry 3 (originally with Raspbian Lite), and got the 11.0.1.
Any attempt to get the 11.2 version by a classical upgrade process
sudo apt-get dist-upgrade wolfram-engine
just answers that I am up-to-date... However I can read in the group lot of posts concerning 11.2 !
How can I get it ? I wouldn't like to reinstall Raspbian, as it is a special image.
Thank you for your help,
Yvesyves papegay2018-05-31T13:46:34ZInterface with Arduino mega in Mathematica?
http://community.wolfram.com/groups/-/m/t/1514918
I am currently attempting to interface with Arduino mega but the basic Arduino functions don't work as they are not specifically for the mega. Any way I can use a serial device open or something else to access this Arduino mega? The Arduino would be used to control stepper motors and other little things. Any tips would be of great help.Adriel Rios Nieves2018-10-15T20:12:18Z