# Tag Info

### When is ##@@@##& more appropriate than ##@@##&?

It's a beginner's error to put @@@ before @@: ...
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### How to keep the code compact in the following case?

I'd recommend to leave all the fluff away and to simply write two loops with a single branching to decide which loop to evaluate. Moreover, it might be a good idea to use boolean arithmetic (i.e. <...
Accepted

### How to make a plot over some external figure?

You can use Prolog and Inset to position the image behind the plot, but some calibration is needed to get correct coordinates. ...
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### How can I write this using fewer variables?

With "Map" and "Accumulate" and "Prepend": ...
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### How can I write this using fewer variables?

No variables (well, except for length) ...
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### How can I subtract and calculate the complement of a pair of sets?

First, do not use capital letters for variables, because capitalized names are used by the system. A set difference, e.g. c-a, is written by: Complement[c, a]. A set union, e.g. of a and b, is written ...
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### How can I subtract and calculate the complement of a pair of sets?

In Mathematica, your P and Q can be written as: P = Complement[b, c] ⋃ Complement[c, a ⋂ b]; Q = Complement[b, a] ⋃ Complement[a, b] ⋃ c; To avoid mistakes when I ...
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### How to calculate different combinations of back and dotted perimeter

All the arc lengths are equal to Pi/6. For example, ...
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### String to expression does not work properly

The smallest fix would be to change the final _ to ___. I.e. the pattern would look like this: ...
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### Dealing with locally defined functions in Module while exporting/importing

You may benefit by using Pure Functions ...
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