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bio website uoregon.edu/~noeckel
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visits member for 2 years, 9 months
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Oct
9
comment Non sequitur in documentation of MemberQ
That historical explanation of why they put the wording in the front section seems to make sense (+1).
Oct
9
awarded  Nice Answer
Oct
9
comment Non sequitur in documentation of MemberQ
I'm going by my knowledge of what all the other functions ending in Q also do. They differ from tests such as Element in that they assign a truth value based on the immediate, explicit structure of the argument. Think of TrueQ: it's very quick to give False because it only gives you True if you give it True first. In other words, functions ending in Q don't ever give "maybe" as an answer...
Oct
9
awarded  Reviewer
Oct
9
answered Non sequitur in documentation of MemberQ
Oct
8
reviewed Close Solve a system of two equations only in Mathematica
Oct
6
comment Explanation for coloring of variables by code editor?
What happens when you check the definition of r by doing ??r ?
Oct
6
comment Explanation for coloring of variables by code editor?
The screenshot has a gap in between line 132 and 136. If you want a real explanation of why r is blue after line 132, you have to post the actual, copyable code sequence without gaps that leads to the coloring you are showing here.
Oct
6
revised Explanation for coloring of variables by code editor?
added 286 characters in body
Oct
6
comment Explanation for coloring of variables by code editor?
I can't tell from the screenshot what happened in your notebook between the point when r was defined and when it reappears later. It may have been cleared in the meantime. Once a variable is subjected to Clear, Remove or =. it will again be undefined and appear blue everywhere in the notebook, even at earlier points. But sometimes it does happen that Mathematica doesn't immediately recognize a previously defined symbol and incorrectly leaves it blue.
Oct
6
answered Explanation for coloring of variables by code editor?
Oct
5
answered Attempt to solve for Differential Equation - Acc, Vel, Pos in (x,y,z)
Oct
5
reviewed Close Formulating a second boundary condition to get an alternative solution to a ODE
Oct
5
reviewed Close Watch File in Directory .NET
Oct
5
comment Mathematica exported movie quality
@JasonB is right - you may want to have a look at this answer where I discuss some other file formats for movie export, and at this answer for how to export image sequences to create the movie externally. However, you can get better result from within Mathematica, too, if you rasterize the image frames at the resolution you like before exporting them. That is discussed here.
Oct
5
revised Using an Image as the Fill/Texture (not background) of a Plot (not polygon)
Second answer due to misunderstanding
Oct
5
comment Using an Image as the Fill/Texture (not background) of a Plot (not polygon)
I thought your main goal was to show the image only under part of the curve, like the colored regions in the sine plot you showed. If not, things are much easier (see other answers). To make the image fit the entire plot, you of course have to make sure that the aspect ratio of image and plot are identical. This could be done (a) by stretching the image, (b) by choosing an image with the right aspect ratio, or (c) by setting the aspect ratio of the plot equal to that of the image. You'd have to decide first which of these options you want. I mention option (a) in my answer.
Oct
5
comment Very serious multiplication bug when subscripts are used
@RolfMertig That's indeed good advice. Subscripts are in general full of pitfalls, especially for people who don't know anything about DownValues... But this seems to be a good test case showing a shortcoming of the parser that looks fixable.
Oct
5
comment Very serious multiplication bug when subscripts are used
@belisarius I confirmed this in version 8 and answered based on what I saw there. I strongly suspect that it's the same in version 10.
Oct
5
answered Very serious multiplication bug when subscripts are used