7.39 March 18, 2014
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Top new questions this week:
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[What does ImageSize -> 1 -> 1
mean?]\url{http://mathematica.stackexchange.com/questions/43820/what-does-i
magesize-1-1-mean}
On the page
http://www.wolfram.com/language/gallery/blur-faces-in-an-image/ the
example code has ImageSize -> 1 -> 1. I am unfamiliar with this
chaining of rules... What does it mean? Note I ...
- asked by PeterR (16 votes), answered by rm -rf (13 votes)
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[Web Browser Screen
Shot]\url{http://mathematica.stackexchange.com/questions/44099/web-browser-
screen-shot}
I have Safari, Opera, Chrome, Firefox and IE installed how might a get a
browser screen shot of a set of HTML code from inside Mathematica(for
any of those browsers)?
(Image is optional)
The ...
- asked by Liam William (15 votes), answered by WReach (23 votes)
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[What is the fastest way to extract a substring from a huge
string?]\url{http://mathematica.stackexchange.com/questions/44175/what-is-t
he-fastest-way-to-extract-a-substring-from-a-huge-string}
I develop an algorithm to find the most common substrings of a given
length n up to a certain distance l in front of a pattern p in a huge
sequence S. E.g. I want to find the most common hexamers ...
- asked by g3kk0 (8 votes), answered by Leonid Shifrin (9 votes)
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[Fast way of finding position of Interval containing an
Integer]\url{http://mathematica.stackexchange.com/questions/43885/fast-way-
of-finding-position-of-interval-containing-an-integer}
I have a large list (about 2.2 million) of pairs of integers. Each pair
defines an Interval[{}]. Given some integer x, I need to find the
position of the interval in my list that bounds x (or ...
- asked by user1375062 (8 votes), answered by Leonid Shifrin (12 votes)
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[How to calcuate the sum of 1/x, where x is an integer not containing the digit 9 and 10,000,000 <= x <= 88,888,888]
\url{http://mathematica.stackexchange.com/questions/43919/how-to-calcuate-the-sum-of-1-x-where-x-is-an-integer-not-containing-the-digit-9}
My code is:
nonine[x_] := If[StringMatchQ[IntegerString[x], "*9*"], False, True];
SetAttribute[nonine, Listable];
tbl = Select[Range[10^2, 888], nonine[#] &];
Total[1.0/tbl]
got out of memory ...
- asked by user2218402 (7 votes), answered by Simon Woods (10 votes)
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[Compile function which calls other functions to
C]\url{http://mathematica.stackexchange.com/questions/44226/compile-functio
n-which-calls-other-functions-to-c}
I have a function which calls other functions and I would like to
compile it to C code. For example:
foo[p_] := 0.7 Exp[-p^2]
f[a_, n_] :=
Module[{s, p, i}, s = 0; p = a;
For[i = 0, i < n, ...
- asked by Danvil (6 votes), answered by halirutan (7 votes)
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[Mathematica-To-MATLAB
Dictionary!]\url{http://mathematica.stackexchange.com/questions/44223/mathe
matica-to-matlab-dictionary}
Is there a dictionary to translate Mathematica functions and commands to
MATLAB?
- asked by Behzad (6 votes), answered by ndetermin (4 votes)
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Greatest hits from previous weeks:
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[Problem with
NonlinearModelFit]\url{http://mathematica.stackexchange.com/questions/2309/
problem-with-nonlinearmodelfit}
I'm having trouble with a non-linear fit:
fit = NonlinearModelFit[data,
y0 + A Sin[\[Pi] (x - xc)/w], {y0, xc, A, w}, x]
where data has about 15 thousand points and looks like this:
The data ...
- asked by becko (14 votes), answered by Oleksandr R. (23 votes)
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[How to find the phase difference of two sampled sine
waves?]\url{http://mathematica.stackexchange.com/questions/11046/how-to-fin
d-the-phase-difference-of-two-sampled-sine-waves}
I'm trying to measure a phase difference between two Sine functions I've
acquired with a computer. I'm uploading one of the .txt files with the
data I'm working with here: txt file. To remove the ...
- asked by Juan (20 votes), answered by bill s (18 votes)
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Can you answer these?
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[RSolve: Errors while solving Partial Difference
Equation]\url{http://mathematica.stackexchange.com/questions/44194/rsolve-e
rrors-while-solving-partial-difference-equation}
I tried solving following partial difference equation in Mathematica by
typing
RSolve[{C[n, k] == C[n-1, k] + C[n-1, k-1], C[n, 0] == 1, C[n, n] == 1},
C[n, k], {n, k}]
but returns the following ...
- asked by user136040 (1 vote)
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[How to apply an rule to factors matching a certain
form]\url{http://mathematica.stackexchange.com/questions/43903/how-to-apply
-an-rule-to-factors-matching-a-certain-form}
Suppose we have many expressions involving irrational ArcTan expressions
(such as ArcTan[Sqrt[3],5]) along with other irrational factors (such as
1/Sqrt[2]).
I want to simplify all of these ...
- asked by Steve (1 vote)
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[How to make noncommutative multiplication agree with commutative
multiplication]\url{http://mathematica.stackexchange.com/questions/44157/ho
w-to-make-noncommutative-multiplication-agree-with-commutative-multiplic
ation}
I need a noncommutative multiplication that is
Associative
Distributive
$A**0=0$, $A**1=A$
Agrees with the commutative multiplication ($A**(k B)=(k A)**B=k
(A**B)$)
I have found a code
...
- asked by 8k14 (1 vote)