8.16 September 10, 2013
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Top new questions this week:
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[Chart illustrating options that affect Graphics/Graphics3D
objects]\url{http://mathematica.stackexchange.com/questions/31745/chart-ill
ustrating-options-that-affect-graphics-graphics3d-objects}
In Mathematica there is a seemingly never-ending list of parameters that
affect the appearance of Graphics and Graphics3D objects: ImageSize,
ImageSizeRaw, ImagePadding, ImageMargins, PlotRange, ...
- asked by kjo (19 votes), answered by Vitaliy Kaurov (18 votes)
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[The dangers of SaveDefinitions --- should this really
happen?]\url{http://mathematica.stackexchange.com/questions/31998/the-dange
rs-of-savedefinitions-should-this-really-happen}
I have been bitten hard by SaveDefinitions -> True. I'll describe in
detail what happened below.
My questions are: Is this a bug? What is the most convenient
workaround?
Consider a definition ...
- asked by Szabolcs (17 votes), answered by Rojo (12 votes)
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[How to get Cases to wrap results in an arbitrary
head?]\url{http://mathematica.stackexchange.com/questions/31754/how-to-get-
cases-to-wrap-results-in-an-arbitrary-head}
A number of functions provide for results to be wrapped in an arbitrary
head. This is very important in cases where the results should not be
evaluated. Take Level as an example:
expr = Hold[{2/2, ...
- asked by Mr.Wizard (17 votes), answered by Mr.Wizard (15 votes)
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[Do Mathematica notebooks include personal
metadata?]\url{http://mathematica.stackexchange.com/questions/31928/do-math
ematica-notebooks-include-personal-metadata}
I am about to send a Mathematica notebook to someone and I would like to
make sure it does not contain any information that could personally
identify me. I would also like to produce pdf files from ...
- asked by episanty (13 votes)
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[How to determine numeric equivalent of Tiny, Small, etc. image sizes
for
Graphics?]\url{http://mathematica.stackexchange.com/questions/31726/how-to-
determine-numeric-equivalent-of-tiny-small-etc-image-sizes-for-graphic}
Is there a way to find the numeric equivalents of Tiny, Small, Medium,
and Large for for ImageSize? In other words, what are the integers t,
s, m, and l such that, for Graphics objects, the ...
- asked by kjo (13 votes), answered by Szabolcs (12 votes)
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[Can ReplacePart be sped
up?]\url{http://mathematica.stackexchange.com/questions/31648/can-replacepa
rt-be-sped-up}
Test case:
data = RandomReal[1, {1000, 1000}];
pos = RandomInteger[{1, 1000}, {5*10^5, 2}];
r1 = ReplacePart[data, pos -> 0]; // AbsoluteTiming
(data[[##]] = 0) & @@@ pos; // AbsoluteTiming
...
- asked by explorer (12 votes), answered by jVincent (4 votes)
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[How to identify chemical substance from
tattoo?]\url{http://mathematica.stackexchange.com/questions/31657/how-to-id
entify-chemical-substance-from-tattoo}
A friend of mine made a tattoo on his chest of some chemical substance
formula.
He challenged us to identify which substance is that. I thought that
perhaps a combination of:
Mathematica image ...
- asked by Zet (12 votes), answered by Sjoerd C. de Vries (18 votes)
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Greatest hits from previous weeks:
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[How to manipulate 2D
plots?]\url{http://mathematica.stackexchange.com/questions/7142/how-to-mani
pulate-2d-plots}
When it comes to visual analysis, large datasets or data with intricate
internal details often makes plotting in 2D useless, as the outcome is
either just a fraction of the full dataset, or no details ...
- asked by Istvan Zachar (54 votes), answered by Istvan Zachar (53
votes)
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[QR Code in shopping cart
handle]\url{http://mathematica.stackexchange.com/questions/26268/qr-code-in
-shopping-cart-handle}
This week, the market people from my work wanted to put QR codes in
shopping cart handles, but when they tested it, the QR code did not
work. I noted that the cylindrical curvature (even small) ...
- asked by Murta (122 votes), answered by halirutan (121 votes)
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Can you answer these?
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[How can I create jpeg images of a given file
size?]\url{http://mathematica.stackexchange.com/questions/31814/how-can-i-c
reate-jpeg-images-of-a-given-file-size}
Cross-posted at Wolfram Community
I would like to have a function makeJPG[megabytes_] that generates
random jpg images of given file sizes with itf filesize (in megabytes)
watermarked on the image ...
- asked by M.R. (3 votes)
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[Understanding the discrepancy between txt file import and export times,
and possibly speeding up
Import]\url{http://mathematica.stackexchange.com/questions/31817/understand
ing-the-discrepancy-between-txt-file-import-and-export-times-and-poss}
I attempted to import a very short .txt file string using the Import
command:
Import["C:\\TestFile.txt"] // AbsoluteTiming
Out: {0.020001, "Test"}
Why does this take 20 milliseconds? Export is ...
- asked by Sparse Pine (1 vote)
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[Setting OperatorSubstitution to false causes Plot's labels of
sufficiently small size not to appear in the specified typeface. Is this
a
bug?]\url{http://mathematica.stackexchange.com/questions/31784/setting-oper
atorsubstitution-to-false-causes-plots-labels-of-sufficiently-small}
If I set OperatorSubstitution to False, the labels of Plot will not use
the typeface specified by FontFamily unless FontSize is more than
certain number.
In this test scenario, that certain number is ...
- asked by Taiki (2 votes)