7.15 Tuesday, September 23, 2014
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Top new questions this week:
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[Maple vs.
Mathematica]\url{http://mathematica.stackexchange.com/questions/60124/maple
-vs-mathematica}
I am reading the document "How Maple Compares to Mathematica" found at
http://www.maplesoft.com/products/maple/compare/HowMapleComparestoMathem
atica.pdf.
On page 15 there is an example where ...
- asked by Milenko Rubin-Zuzic (16 votes), answered by Mr.Wizard (22
votes)
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[StringCases is Confused with Patterns in Version
10.0.1]\url{http://mathematica.stackexchange.com/questions/60156/stringcase
s-is-confused-with-patterns-in-version-10-0-1}
I observed the following with StringCases when trying to use
rules/patterns. Here is a screenshot of the behavior:
Not only is the pattern highlighted in red, hovering the mouse over it
claims it's ...
- asked by RunnyKine (14 votes)
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[How can I restore the old `ImageCompose`
behaviour?]\url{http://mathematica.stackexchange.com/questions/60048/how-ca
n-i-restore-the-old-imagecompose-behaviour}
Prior to version 10, if ImageCompose was used to overlay a partially
transparent image region over a completely transparent image region, the
result would keep the colour of the overlay. Like this:
...
- asked by Simon Woods (13 votes), answered by Karsten 7. (3 votes)
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[Better way to test that a matrix is
upper-triangular?]\url{http://mathematica.stackexchange.com/questions/60081
/better-way-to-test-that-a-matrix-is-upper-triangular}
Today, I got to thinking about how to test that a matrix was
upper-triangular. So I had a try at it.
Algorithm
$\quad \quad a_{ij}=0 $ Or $i \leq j$ $\Rightarrow$ $True$
My solution is
...
- asked by Tangshutao (13 votes), answered by Mr.Wizard (9 votes)
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[How to get Company Logo or
Image]\url{http://mathematica.stackexchange.com/questions/60041/how-to-get-
company-logo-or-image}
I can see that companies have a logo in Wolfram|Alpha when I type in
their name but I can't get them in Mathematica.
For example searching for Apple, Inc. in W|A one of the outputs is the
Apple logo. ...
- asked by Edmund (12 votes), answered by eldo (15 votes)
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[How to make a 3D topographic
globe?]\url{http://mathematica.stackexchange.com/questions/60427/how-to-mak
e-a-3d-topographic-globe}
I've made some attempt with this dataset of elevation.
But I have some trouble with ListSurfacePlot3D, which can not show the
globe correctly:
And I've checked that the data is out of problem, ...
- asked by RexDiego (11 votes), answered by bobthechemist (10 votes)
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[Is there a better way to "grow" black
tulips?]\url{http://mathematica.stackexchange.com/questions/59905/is-there-
a-better-way-to-grow-black-tulips}
I used the following clumsy way to obtain a bundle of black tulips. Is
there a better way to do so?
im = Import["http://i.stack.imgur.com/qclHT.jpg"]
cols = DominantColors[im, 9]
rim1 = ...
- asked by Putterboy (11 votes), answered by ybeltukov (17 votes)
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Greatest hits from previous weeks:
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[Can Mathematica do symbolic linear
algebra?]\url{http://mathematica.stackexchange.com/questions/3242/can-mathe
matica-do-symbolic-linear-algebra}
For instance, is there some way I can say "let A and B be arbitrary real
$m\times n$ and $k\times m$ matrices,
Simplify[Transpose[Transpose[A].Transpose[B]]]" and Mathematica would
simplify it to B.A?
...
- asked by nikie (24 votes), answered by helen (12 votes)
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[Why round to even
integers?]\url{http://mathematica.stackexchange.com/questions/2116/why-roun
d-to-even-integers}
According to the Mathematica help:
Round rounds numbers of the form x.5 toward the nearest even integer.
For example:
Round[{0.5, 1.5, 2.5, 3.5, 4.5}]
gives
{0, 2, 2, 4, 4}
What's the ...
- asked by wxffles (26 votes), answered by Per Alexandersson (22 votes)
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Can you answer these?
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[Solving a system of two nonlinear equations with many symbolic
parameters]\url{http://mathematica.stackexchange.com/questions/59930/solvin
g-a-system-of-two-nonlinear-equations-with-many-symbolic-parameters}
I have two nonlinear equations with two unknowns, $x$ and $y$, and many
symbolic parameters, $a, b, c, d$. They look someting like:
$\frac{1}{x}(1+x)^a (1-b)(cx+dy)=0$
...
- asked by jim (2 votes)
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[Example in Help File does not evaluate as
claimed]\url{http://mathematica.stackexchange.com/questions/60281/example-i
n-help-file-does-not-evaluate-as-claimed}
In the help file, under BellB, I read at 'Properties and Relations':
"Sum can give results involving BellB ":
Sum[k^n/k!, {k, 0, Infinity}]
E BellB[n]
but, in my version 10.0.1.0 it does not ...
- asked by Wouter (2 votes)
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[How to get the centroids of the ClusterComponents
function]\url{http://mathematica.stackexchange.com/questions/60301/how-to-g
et-the-centroids-of-the-clustercomponents-function}
I use the ClusterComponent function to get the k-means clustering:
Needs["HierarchicalClustering`"]
cl = ClusteringComponents[data, 4, 1,
DistanceFunction -> CorrelationDistance, Method -> ...
- asked by user13675 (2 votes)