Questions tagged [system-variables]
The system-variables tag has no usage guidance.
19
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Items known by CurrentValue
CurrentValue can be used to poll the state of numerous system values such as the mouse position. Its help page doesn't list all possible items, though. An item like ...
6
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5
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Is there an analogue of the Variables command for general expressions? [duplicate]
The command
Variables[poly]
gives me a list of all variables that appear in the expression poly, which involved sums, ...
- 1,088
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2
answers
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Where can I permanently modify $Path?
I've quite forgotten: what file does one modify in order to add directories to $Path globally? Specifically, I want to include ...
- 12k
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2
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Catching MachineUnderflow in Version 11.3
Ilian's answer to question 72229, involves
SetSystemOptions["CatchMachineUnderflow" -> False]
Evidently, this worked in earlier versions of Mathematica, but ...
- 61.9k
17
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1
answer
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Can one effectively edit a Front End Resource that is already loaded?
A number of special definitions are loaded from .tr files on Front End initialization and are accessible via FrontEndResource. ...
- 273k
5
votes
2
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Syntax highlighting conflict
I'm trying to syntax highlight this expression: x=$\sqrt{\pi }$//N and from various sources I've learned that x (the assigned symbol) belongs to context Global while the Pi and N belongs to System. So ...
- 5,121
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How to set UnitSystem permanently
I would like to set the system of units ($UnitSystem) permanently to "Metric".
I know that I can do
...
- 37k
11
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4
answers
327
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How to change the variables Qi's to Ri's in one or two steps
I was wondering if there is a command in Mathematica to change all the following Qi's to Ri's? For example, change Q1 to R1, Q2 to R2, etc.
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- 319
9
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2
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How to set the timeout value for *Data functions
I haven't measured this precisely but it seems the default timeout value for retrieving EntityValues with *Data functions is in ...
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3
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variable K cannot be deleted
If a value is assigned to a variable that is named by capital K it cannot be deleted. This effect can be observed directly after start of the program.
Is this a bug?
- 593
17
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3
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How to programmatically ask if Mathematica is running as an administrator
To avoid execution problems in a program I need to know if Mathematica has been "Run as administrator". What would be the cleanest way to programmatically getting this information?
- 1,697
10
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Why do DateList, DateString, and AstronomicalData ignore $TimeZone?
My reading of the documentation for DateList and DateString lead me to believe that both functions use ...
- 12.9k
5
votes
1
answer
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Is it safe to change the value of $TimeZone?
I'd like to configure some of my notebooks to assume all calculations using dates, times and locations (notably AstronomicalData , but others too) take place at the ...
- 12.9k
5
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1
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Setting $RecursionLimit crashes Mathematica 10
I have encountered what I shall presume is a bug: setting $RecursionLimit repeatably crashes the Mathematica 10 kernel:
...
- 273k
3
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3
answers
328
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Accessing temporary value of a Nest evaluation
The function Nest[] must store the temporary values in the memory somewhere (those values that would form the entries of the list which is returned by the ...
- 333
1
vote
1
answer
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How to make the variables in $init.m$ not impact the autocompletion
The autocompletion is very convient in Mathematica,but it will make one annoying sometimes when you have a ton variables.I give a scene I encounter.I usually make ...
- 27k
1
vote
1
answer
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How to understand and use DSolve solution
This equation is simple to DSolve in Mathematica, but I don't know how to use and understand solution.
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- 1,129
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1
answer
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Choice of variables name affects the behavior of expression evaluation
I tried to expand this polynomials. With x, it is increasing with the right order, however with b it is in a random order. The only difference is that I change b to x and it works.
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How can I globally change $Path permanently? [duplicate]
I have two packages that I would like to append to $Path. I have looked at this link for help but after I quit Mathematica, I have to repeat the process again.
Where can I permanently modify $Path?
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