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Nov
28
comment How to use Message with an error string without predefining it first?
@Karsten7. Yes, I could do that. But it is more complicated, and according to accepted answer in what-are-the-best-practices-most-common-idiomatic-ways-to-report-errors-in-m this is not recommended way, which I agree. Someone have to catch the error. I was looking for simple basic method, and I think Message[] does the job well.
Nov
27
comment How to integrate a table?
You did not say what the x/y data is, assuming the above is y, so x will be {1,2,3,4}. Hence extrapolation is used and result is not as good as interpolation.
Nov
27
comment Why my differential equations become True?
I think it is a Mathematica design error to store derivative of a user symbol in the system context. Everything relating to user symbols/variables should be kept outside system context. Nothing should leak outside like with this example.
Nov
27
comment How to combine manipulate and eventhandler
Well, I move the sliders and nothing happens for me. Cube do not move at all. V 10.01 on windows 7. Changed item from 1 to 2, clicked enter, etc.. move slider, cube does not move.
Nov
27
comment How to combine manipulate and eventhandler
Is something supposed to happen when the sliders are moved? It will help to explain a little bit what this is supposed to do? V10, and nothing changes for me when I moved the slides or click Enter button?
Nov
26
comment How to combine manipulate and eventhandler
no need to put DynamicModule inside Manipulate. Manipulate itself is DynamicModule.
Nov
26
comment How to use a Butterworth bandpass filter to generate a chirped signal
please do not use UpperCaseFirstLetter for your functions, it confuses one looking at it, since it appears as if it is a Mathematica build-in functions.
Nov
26
comment Symbolic integration conditional bug?
If the limit is symbol, there has to be a convention. THis is what we do on paper. How would you integrate $\int_{0}^x \,dt$ ? Will the answer be $x-0$ or $0-x$ ? any way, that what I think.
Nov
26
comment Symbolic integration conditional bug?
see help on Integrate., it says Integrate[f,{x,Subscript[x, min],Subscript[x, max]}]
Nov
26
comment Symbolic integration conditional bug?
but when writing Assuming[x > 0, Integrate[1/t^2, {t, 1, x}]], then in here 1 is min, and x is max. According to help. Hence x has to be greater than 1. In the second example, when you wrote Integrate[ 1/t^2, {t, 1, 1/2} ] here you are giving numerical values for the limits, so it knows that the upper limit is less than the lower limit?
Nov
26
comment Numerically Simulating a Simple Differential Equation: RC Circuit
why do you need a step function for? Since solution to ODE, which is the current is zero before $t_0$ for any $t_0$ any way. You could always shift the solution to right afterwords if you want. But may be I am missing something about your description.
Nov
26
comment Why `Plot` does not obey the `AspectRatio` specification?
I just told M to make the origin of the axes (0,0) instead of what it was before, so you can see more clearly that AspectRatio -> Automatic was doing what you wanted. Without telling M where the origin of the axes is, it decides itself. See help on AxesOrigin for more information.
Nov
25
comment Why `Plot` does not obey the `AspectRatio` specification?
It is the same, try this to see it more clearly it is the same Plot[PDF[BetaDistribution[0.8, 0.8], x], {x, 0, 1}, {Filling -> Axis, AspectRatio -> Automatic, AxesOrigin -> {0, 0}}] screen shot !Mathematica graphics
Nov
25
comment Physics Lab with mathematica
the first thing to do is import the data to M, reference.wolfram.com/language/ref/Import.html so work on this part. Once you get the data to the notebook, then the rest is easy.
Nov
25
comment How to make Graphics3D with multiple lighting sources being rendered faster
You must be talking about openGL viewer by Jens-Peer Kuska, who was a Mathematica expert (sadly passed away when only 45 years old). I remember using it also. I do not know if it would have helped or not, may be. If you want to do heavy duty 3D simulation, I do not think M is the right tool. Too bad, since its 3D API is really nice and well designed and easy to use to build 3D objects with, but if it is slow to render, none of this matters at the end. Here is the openGL viewer manual
Nov
25
comment How to make Graphics3D with multiple lighting sources being rendered faster
rendering speed of 3D in M is known to be slow, I complained about this for long time. The more data you have the slower it gets. Here is a post How to improve performance of Graphics3D rendering with Dynamics Notice no reply and nothing on this post. No body seems to care about this. Sometimes you can speed things up by removing some 3D stuff, like opacity will slow things, etc... but the whole problem is that M renders 3D slow. That is why I stopped using Manipulate for 3D physics simulation. Too slow.
Nov
25
comment How to turn an expression into a number
try again posting the code as it is not readable now. select the cell, convert to inputForm, then copy it as text and paste. You seem be to missing some "\" on symbols used.
Nov
24
comment Is the “Table” function limited in number of elements it can compute?
Try with ";" after the Table command. Does the command complete?
Nov
24
comment Plotting ODE solutions with two parameters
use Manipulate, make sliders for the parameters, and do DSolve inside Manipulate and plot the solution(s).
Nov
24
comment Injecting list of controls into manipulate
@RolfMertig no problem. what I meant by not possible, is the way the OP was doing it. May be be V11 the Wolfram language will add support for this (i.e being able to make function calls to build the controls themselves) But I am still looking for an easy to use debugger build right into the notebook itself and for line numbers! Maybe will have to wait for V20 for these :)