Problemania

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bio	website	problemania.org
	location	Problemania
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visits	member for	1 year, 4 months
	seen	Jun 7 at 17:45
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A moderator at Wiki site http://problemania.org where a group of enthusiasts enjoying sharing the fun solving mathematics, physics, and computing problems. We primarily work on problems found in college/grad school text books.

Web page: http://problemania.org

Twitter: http://twitter.com/#!/problemania

Github: https://github.com/Problemania

E-mail: problemaniac@gmail.com ( NOT problemania@gmail.com )

	1,195 reputation	bio	website	problemania.org	visits	member for	1 year, 4 months
317 badges		location	Problemania		seen	Jun 7 at 17:45

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May 7	comment	How to make a notebook not savable? It's similar to `r` and `w` permission settings. `Saveable` is just more flexible for Mathematica notebooks as users can still evaluate things. Aren't Mathematica's documentation notebooks set that way or something very similar?
May 7	comment	How to make a notebook not savable? So, it's impossible to do this from menu for the current in-focus notebook?
May 7	comment	How to make a notebook not savable? So how to do this from menu (not by evaluating a command)?
May 7	comment	How to make a notebook not savable? If "Save As" is used and the new file name overwrites the current file, then it means the users deliberately wants to do that?
Jan 27	comment	What's the analogue of UML in Mathematica land? You can argue that this is an advantage in some cases, but disadvantage in some other.
Nov 16	comment	How to read data file quickly? Any idea how to make this also work on Windows?
Oct 29	comment	Implementing a For (?) or series or loop (?) for individual results for every x to n Can't you import the whole spreadsheet (.xls etc.) and manipulate the data in Mathematica session then write them back, rather then read 2 rows each time?
Oct 29	comment	How to find local minima of a multivariate function with singularity? I'm still not exactly sure why converting `Indeterminate` to `$MaxMachineNumber` is safe that no $-\infty$ will not be mistakenly converted.
Oct 29	comment	How to find local minima of a multivariate function with singularity? Could you explain a little that why when Sigmoid returns exactly 0 or 1, there will then be a `Indeterminate`? Is it that `y_i - Sigmoid[...]` is somehow used as a denominator in the computation?
Oct 29	comment	How to find local minima of a multivariate function with singularity? @acl: Added data set.
Oct 10	comment	What's a good data structure to represent a, b, a and b, a or b? Had to admit, I didn't expect `MemberQ["a" && "b", "a"]` to return `True`. Ok. Thanks!
Oct 10	comment	What's a good data structure to represent a, b, a and b, a or b? If using `{{"a", "b"}}` and `{{"a"}, {"b"}}`, i can use `MemberQ` to test existence of "a" and/or "b". If using `"a" && "b"` and `"a" \|\| "b"`, what's good way to do such tests?
Oct 10	comment	What's a good data structure to represent a, b, a and b, a or b? Expressions `"a" && "b"` and `"a" \|\| "b"` are a little harder to compute with than say `{{"a", "b"}}` and `{{"a"}, {"b"}}`.
Oct 10	comment	What's a good data structure to represent a, b, a and b, a or b? @celtschk Thanks, you seem to understand what I want and have trouble to explain.
Oct 10	comment	What's a good data structure to represent a, b, a and b, a or b? I'm sorry. The `foobar[]` I am thinking is a little like `Checkbox[]` except I don't want the UI aspect. It can represent a state/type. That's it. And why not just 1, 2, 3, 4? Because it will then need another structure to explain what 1, 2, 3, 4 mean respectively. Other functions can do different things based on whether a and/or b is present in the 'state'.
Oct 10	comment	What's a good data structure to represent a, b, a and b, a or b? @rm -rf I added additional info. Is it sufficient? BTW, your user name sounds dangerous. Never do it in real life.
Sep 11	comment	How to avoid nested With[]? With the potential effects of these different attributes on the program unknown, I think I'd better just use `Module[{v1, v2}, v2=f[v1]; g[v1, v2]]`. Thanks!
Sep 11	comment	How to avoid nested With[]? Just hide the nested `With[]` under hood of a new symbol?
Sep 10	comment	How to make a drop-down selector? I don't need to show anything such as a plot that depends on the value selected in the drop-down. Rather, I just need a state-recorder that knowns the user's selection in the menu which can later be read out from the notebook.
Sep 9	comment	How to write a UTF-8 file? Really? No wonder. My guess is Export[file, ...] internally will create file handle any way and using file handle directly probably just mean a replacement didn't occur. It might be an accident due to implementation details.