16
votes
Wolfram says sum diverges, but Mathematica gives a numerical value for infinite sum
As the message shows, NSum works on limited recursions. Mathematica does not consider the "mathematical converge" when it works on NSum. Therefore Mathematica finds that this sum converges too slowly, ...
- 1,993
15
votes
Accepted
Wolfram says sum diverges, but Mathematica gives a numerical value for infinite sum
When a command has issues, it is a good idea to check the Possible Issues section of the doc page for the command, in this case NSum. Two of the issues apply to ...
14
votes
Accepted
All the food WolframAlpha knows about
Go to a new cell in a notebook and write "=", this will create an orange equality sign in the beginning of the cell. This means that you have entered the free form input mode. Write the name of a food ...
- 70k
12
votes
Accepted
Why does Mathematica's date for the battle Agincourt differ from the US Navy's?
The date is different because Wolfram Alpha is wrong about when the Battle of Agincourt took place.
Alpha is returning 25 October 1415 in the Gregorian calendar as the date of the battle, but the ...
- 12.8k
12
votes
Accepted
How to make a picture grid of all Nobel Laureates in physics?
Here's something to get you started down to path of scraping the somewhat larger individual pictures from the Nobel website:
...
- 65.8k
11
votes
Unit Discovery: Is this some sort of a sick joke?
A bit too long for a comment...
My best guess is that WolframAlpha["earth's gravity", "MathematicaResult"] is simply rounding to too few digits. It returns ...
- 35.5k
11
votes
All the food WolframAlpha knows about
I remember from last years conference (Wolfram Technology Conference 2015) that there was a presentation on food entities. It doesn't seem to have been recorded but you can get the presentation (Food ...
- 41.7k
11
votes
Accepted
Proteins, ProteinData, WolframAlpha
Here's a workaround that directly queries the PDB search API and returns the first num search results as a Dataset[]. The ...
- 123k
10
votes
Accepted
Differing answers when comparing Wolfram Alpha and Mathematica v.10.2
For large enough bounds, NSum is used. Compare timings:
NSum[(-1)^(n + 1)/n, {n, 1, 100000}] // AbsoluteTiming
...
- 35.5k
10
votes
Accepted
10
votes
Accepted
Step by Step for Generalized Eigenvectors?
This is an update to make it handle geometric multiplicity>1.
When an eigenvalue has geometric multiplicity=1, then this will use the basic method of solving $(A-\lambda I) v_2 = v_1$ to find the ...
- 137k
9
votes
Accepted
Can Mathematica solve functional equations with nested variable?
It doesn't seem there is a one line solution but we can adapt W|A to give a result similar to DSolve and friends.
...
Kuba♦
- 136k
9
votes
How to ask WolframAlpha to find 'x such that p=32*x+1 is prime'
General
There are as many solutions as prime numbers
If you Solve for $x$
Solve[32 x + 1 == p, x]
...
- 36.2k
8
votes
Accepted
Is it possible to simulate a solved example in Wolfram for free, How?
I do not use the Wolfram Language at Wolfram Alpha since the syntax is a little different and I have access to Wolfram Mathematica which I prefer to Wolfram Alpha.
If you have Wolfram Mathematica, ...
- 137k
8
votes
Proteins, ProteinData, WolframAlpha
A quick and dirty is to download the PDB file from the main PDB database (eg
Bovine rhodopsin), use the Download button/dropdown on the top right and select Text format
then
...
- 784
8
votes
Proteins, ProteinData, WolframAlpha
Try this here
Import["http://www.rcsb.org/pdb/download/downloadFile.do?fileFormat=pdb&compression=NO&structureId=1U19", "PDB"]
- 112k
8
votes
Accepted
Confusion in finding the definite integral
Precision issues. Use one of the following instead.
Symbolic integration:
...
- 4,231
8
votes
Accepted
Why can't I plot two graphs on the same plane in WolframAlpha?
WolframAlpha["plot x^2+y^2=6 and x arctanx -x +y arctan y=0"]
- 151k
8
votes
Accepted
Why does MMA fail to find a solution but WA does?
First, my stab at W|A gave a different output than the OP (something like what I show for Reduce below, in fact).
Second, I'm not sure how to read the W|A output ...
- 233k
8
votes
Accepted
Exporting results containing Entities to JSON?
You can use "ConversionFunction" / "ConversionRules" for ...
Kuba♦
- 136k
7
votes
Accepted
How to create a find-and-replace code in Mathematica?
You can use StringReplace to define a function to make the replacement and use FixedPointList to get the result of applying the ...
- 384k
7
votes
Accepted
Convert WolframAlpha output to $\LaTeX$
You can do the following. Once you get the output in Wolfram Alpha web page, say you have typed solve y'+x=0, then in the output window, hover the mouse there, and ...
- 137k
6
votes
Facebook Report is not available
Facebook has deprecated the API that Mathematica relied on to gather this information. Official source.
- 70k
6
votes
How to create a new "person curve"?
Simon Woods' cool answer is based on two independent discrete Fourier transforms: one for $x$, one for $y$. This answer differs in that it uses only one, but on complex values. It's it not a very big ...
- 14.2k
6
votes
Accepted
I use WolframAlpha within Mathematica; would there be any advantage to buy Wolfram|Alpha PRO?
W|A Pro over Mathematica:
No API call limits. 3,000 for student Mathematica.
Using Wolfram's hardward. If you run on a slow PC, tablet, or phone.
If you have access to Mathematica, W|A Pro provides ...
6
votes
How to ask WolframAlpha to find 'x such that p=32*x+1 is prime'
If you have Mathematica, you can use the FindInstance function, which by definition provides one (or many) solutions to a particular equation:
...
- 4,231
6
votes
Conditional Summations
Sum[Binomial[35, n]*100*If[n > 10, 10, n]*(.1^n*.9^(35 - n)), {n, 0, 35}]
- 31.2k
6
votes
Accepted
Difference between free-form input via WolframAlpha[] and CTRL+=
Here is the summary from original M8 release page:
This guide should also be useful: Free-Form & External Input. While both things you mentioned are a part of integration of Wolfram|Alpha (W|A) ...
- 71.9k
6
votes
step-by-step solution unavailable (( possible intermediate steps ))
While Mathematica and Wolfram Alpha can't produce the step-by-step for most of the integrals, there is a Rubi package for integration is available:
...
- 3,857
Only top scored, non community-wiki answers of a minimum length are eligible