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1d
comment Trouble using Manipulate and NDsolve for coupled ODE's
I should note (for clarity) that the proper syntax for Manipulate is: Manipulate[expr, 'controls'], where 'controls' can take various forms (like lists, Control[XXX], etc...). Arguments in WL are separated by commas, and the first argument to Manipulate is the expression to be manipulated. The problem in the OP was that the first argument was actually NDSolve[XXX] and not the CompoundExpression they actually wanted.
1d
comment How to prevent tiny complex errors in Integrate?
Not addressing why you see this particular behavior, but if you want an exact analytic answer, you need exact inputs. 6.5 is not an exact number.
Dec
18
comment Module function corrupts string?
Unless an explicit Return is used, the value returned by For is Null.
Dec
18
comment Module function corrupts string?
it is not a hack to use proper syntax
Nov
25
comment What quantity is this “length” called?
Perhaps you really want a test for the result being a List or not? Then you might look at ListQ (undocumented tho).
Nov
7
comment Selection bugs make Mathematica 10 unusable
support.wolfram.com/kb/12464
Oct
2
comment Replacing columns of a matrix with zeros
I suppose you could do something like this then MapAt[#*0&,list1,{All,1;;3}]
Oct
1
comment Outputting numbers symbolically
Inactivate[Table[2^n, {n, 1, 5}], Power] (I am not obsessed with Inactive I promise)
Oct
1
comment Strange style conversion indicator appeared when type “a Pre”
From reference.wolfram.com/language/ref/CodeAssistOptions.html it looks like the option is "AutoConvertEnable".
Oct
1
comment How to regress negative log?
Something like NonlinearModelFit[data, -p2 Log[p1 x],{p1,p2},x] where p1 and p2 are parameters?
Oct
1
comment Spherical parametric plot
If you have version 9+ you can use: ParametricPlot3D[Evaluate[CoordinateTransform[ "Spherical" -> "Cartesian",{2 Cos[t]+Sin[t],t,Sin[10 t]}]],{t,0,Pi/2}]
Oct
1
comment How to simplify symbolic matrix multiplication using the associativity of scalar multiplication?
This may be too specific: Thread[(2 A).(3 B), Times] /. Dot[a_?NumericQ, b_?NumericQ] :> a b
Sep
12
comment Join decimal part
just beat me to it, yours is the same as mine (essentially):toDecimal[a_, b_] := N[a + (-1)^Sign[a] b 10^(-IntegerLength[b])]; list /. {a_, b_, c_, d_} :> {toDecimal[a, b], toDecimal[c, d]} (* {0.1, -2.259} *)
Aug
27
comment Numerical value of physical constants Mathematica 10
you can also use QuantityMagnitude to get the value out.
Aug
27
comment Numerical value of physical constants Mathematica 10
or In[647]:= UnitConvert[Quantity[1, "PlanckConstant"], "eV*s"] Out[647]= Quantity[4.135668*10^-15, "Electronvolts" "Seconds"]
Aug
27
comment Numerical value of physical constants Mathematica 10
what would you like the result to be, i.e. which units should it be with respect to?
Aug
22
comment Window ▶ Show Handwriting Input
Have you turned on the "Tablet PC Components" in Windows 7?
Aug
5
comment Integral too slow and with conditionals
use assumptions Integrate[x/(x^2 + y^2)^(3/2), {y, -a, a}, Assumptions -> (x | y) \[Element] Reals && x > 0 && a > 0]. This is likely a duplicate, but I can't find which one.
Aug
5
comment No menu in Mathematica 10 under Ubuntu 14.04
What is the result of the following? AbsoluteOptions[EvaluationNotebook[], WindowElements]
Jul
30
comment Why does Fourier give a shifted frequency?
@xslittlegrass, actually it was the second part in the answer: "in addition, the discrete fast Fourier transform assumes periodicity."