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Apr
12
comment predator prey model with prey refuge
I see few demos here on this subject demonstrations.wolfram.com/search.html?query=predator%20prey
Apr
11
comment How can I get precise frame rates in dynamic?
@kguler I do not know. This is how it showed up on my console: screen shot !Mathematica graphics
Apr
11
comment Programming paradigm change
When I go to that link you posted, using firefox, I see empty boxes there for the code. Only when I move the mouse over the box, will the code show up there. Same with IE and Chrom. Very strange and confusing web site this reddit is.
Apr
11
comment How can I get precise frame rates in dynamic?
Your code does not run on V 9.01, I get error ArrayPad::mlens: Padding amount {10-orp[here ],6+orp[here should be an integer, pair of integers, or list of pairs of integers. screen shot !Mathematica graphics
Apr
9
comment Is it possible restore initial values after modify a control in manipulate?
I removed that. Not needed actually here. Updated the code.
Mar
31
comment For loop efficiency
you are not supposed to use loops in Mathematica (I know it is hard coming from matlab and fortran and C to avoid loop thinking), but it is for your own good :)
Mar
30
comment Writing a simple application: interactive quiz for multiplication table practice
what, no Manipulate? :)
Mar
30
comment Needs, Get and <<
Get and << are the same thing as far as I know. Needs calls Get only if the package was not loaded already. If the package is already loaded, then Needs is smart enough to know this and will not reload it. Sometimes reloading the same package again might cause a problem (that is what I read somewhere). Not sure of why and how. So, it is better to use Needs I would think, just in case the package itself was not designed to be aware of itself being loaded before, or it assumed it was not loaded. I think a well designed package should not cause a problem with multiple Get.
Mar
30
comment Why won't my function plot?
@Szabolcs the first thing I did is convert it to Piecewise. ofcourse, that is the better way to do it. g[z_] := Piecewise[{ {5*(Min[0.1, z] - Max[0, z - 1]), 0 <= z <= 0.9},{5*(Min[0.1, z] - Max[0, z - 1]) + 5*(Min[1, z] - Max[0.9, z - 1]), 0.9 <= z <= 1.1},{5*(Min[1, z] - Max[0.9, z - 1]), 1.1 <= z <= 2},{0, True}}]; Plot[g[z], {z, 0, 2}] But for the plot issue, it did not make a difference. I think this is a bug also.
Mar
30
comment Writing a simple application: interactive quiz for multiplication table practice
this section in the demonstration site has lots of similar apps demonstrations.wolfram.com/… You can see all topics here demonstrations.wolfram.com/topics.html here are some on use of multiplication table demonstrations.wolfram.com/…
Mar
30
comment Why won't my function plot?
Plot[g[z], {z, 0, 2}, PlotRange -> Full] works also
Mar
29
comment Please explain this short code
Look at FullForm of Rule: FullForm[a -> 3] gives Rule[a,3] so x /. Rule[f_, _] :> f just says to extract the first argument of the rule (the thing before the arrow). So rules = {"a" -> 99, "b" -> 100}; rules /. Rule[f_, _] :> f returns {"a","b"} see reference.wolfram.com/mathematica/ref/Rule.html
Mar
29
comment How to make Mathematica Simplify?
You can't take derivative with respect to a number. so not sure what q1'[3] is meant to represent. Also, If[Norm[v] > 0, v/Sqrt[Norm[v]], 0] return the result you show, since it is passed a symbolic expression. You are mixing symbolic with numerical computation in strange way.
Mar
25
comment How do we solve third order nonlinear differential equation f’’’+ff’-f’2-Re2 f’=0
You can start with DSolve. If that fails, then try NDSolve.
Mar
25
comment How to differentiate between formatted and unformatted strings?
@rasher thanks, I see it now. But for me it is just a string. Anything with a starting " and ending " is a string. But I understand now the OP wanted to parse/detect it to see if it it contains Mathematica specific content. Ok.
Mar
25
comment How to differentiate between formatted and unformatted strings?
@rasher, ok, I just never heard or seen something called "internally formatted string" reading Mathematica documentation. I just googled this and it turned no hit. But may be I just need to look harder.
Mar
25
comment How to differentiate between formatted and unformatted strings?
what is "internally formatted string"? A string is a string. Why would it matter what is inside it? I did not know that Mathematica had 2 kinds of strings before.
Mar
24
comment FrameTicks and Ticks on Axes in Same Plot
I assumed they wanted on the lower x-axis the same ticks as the top axis (i.e more ticks), but in addition to add those 2 edges special tick labels they had. (you are right, it would have been better to have xt[t] there also). may be OP can clarify.
Mar
24
comment FrameTicks and Ticks on Axes in Same Plot
I understand that what you wanted, but when Frame->True then Ticks is ignored and not even looked at. So there is no point of even having it there. That is what I mean. Try Plot[Sin[x], {x, -Pi, Pi}, Frame -> True, Ticks -> {{1, 1}}] so the actual ticks will have to come from FrameTicks which you already specified.
Mar
24
comment FrameTicks and Ticks on Axes in Same Plot
Since you said Frome->True then you need to use just FrameTicks not Ticks.