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Example: ...
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Boxes may be represented as expressions or as strings. How can I convert between the two forms? In particular, how can I convert from the string representation to the expression representation? ...
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I would like to know the name of the current function from within that function. For example, consider the following code ...
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### Mathematica Destructuring

Context I'm writing a function that look something like: ...
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### Why does array packing in Table behave like this?

Consider the following example, which generate two identical arrays. Why sometimes the array is packed and sometimes it doesn't? And why they perform differently? Here the arrays are packed: ...
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In response to my question How can I get the unchanged Box form of an arbitrary expression? John Fultz answered with a method using the hilariously named ...
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Introduction I often have the problem that in an expression, I want to change an option. If we are sure the option is not present, we could simply use ...
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### How to take a part from a list without evaluating it

Consider I have a list l ...
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I understand Mathematica can't assign the results of a Solve to the unknowns because there may be more than 1 solution. How can I assign the 4 values of following result to variables? ...
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### How to create symbols from strings and set values for them?

I am trying to convert a list of string names into symbols, which will then be used to store data. I have 24 files (where the name of each file is a member of the list mentioned above) that I need to ...
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### Where can I find examples of good Mathematica programming practice?

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ...
9k views

### How to plot periodic function's graphic?

How to plot periodic function's graphic? For example, $f(t) = t$ when $-5<t<5$ and $f(t+10) = f(t)$. ...
481 views

### Why can't I inject expressions in Compile using (only) With

Generally speaking, With can be used to inject into arbitrarily held expressions, for example: ...
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### Splicing a list of arguments into a function with Sequence

Not sure if this has been asked, but I have a fairly simple operation that I don't know the syntax for. Say I have an array with some values, and a function f that accepts an arbitrary number of ...
194 views

### Operations on expressions within Hold

I want to convert {Hold[1 + 2], Hold[3 + 4], Hold[5*6]} into Hold[{1 + 2, 3 + 4, 5*6}]. I have tried ...
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I store a reference to the association in a held expression in a variable: a=<||>; b=Hold[a]; And in the code, I want to do manipulations with the original ...
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If you use Plot like this, Plot[Sin[x], {x, 1, 5}] it produces the correct Sin graph ...
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I would like to plot a function but have a domain defined elsewhere as follows: xrange = Sequence[0, 2π]; Plot[Sin[x], {x, xrange}] However, this doesn't work ...
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I have been playing with slightly above trivial code manipulations in Mathematica. I thought Mathematica would be great for this kind of work because of rule replacement and expression manipulation, ...
304 views

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Seems to me that VerificationTests are a bit verbose: ...
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Goofing off on a prior question, I was fiddling with other methods, which led me to the need to inject a constructed set of iterators into a table construct. Now, ...
266 views

### different situations with Compilation of ConstantArray

First, we load some tools related to Compile for analysis. ...
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I would like to override the behavior of Dot, so that Dot[u,v] will return a scalar instead of a 1x1 matrix in the case that the ...
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As part of a calculation I need to do something like this Evaluate[{aaa, bbb, ccc}[[ index]]] = {1, 2, 3, 4, 5} so if index is ...
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Being functional, and having no "quotation", i.e. essentially treating data and programs semantically same, Mathematica seems naturally capable of doing metaprogramming. But could anyone construct a ...
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I want to return a Hold expression but with some parts pre-evaluated. The easiest way to explain this is probably through code example. Here is what I have ...
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I would like to write a procedure with the signature: Foo[vars, params] which produces a Manipulate object. The procedure ...
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I defined a function f like f[x___, y_] := something; and if xs and ...
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I would like to get a list of variable names as strings. For example, x = 1; y = 2; Map[SymbolName, Unevaluated /@ Unevaluated@{x, y}] {"x", "y"} This works ...
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Since Mathematica deals with Head[a, b] as an expression in this way The first Part of Head[a, b] is ...
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If I have a function, that returns a function, for example: f[a_] := a^2 * # & then f == 3^2 # & Is there a way ...
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I have a list of variables variables={a,b} and a list with values values={1,2}. I'd like to define a function using the ...
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I have an estimation routine I have coded up, I want now to do some tests on it where I pick a particular parameter and run the estimation for differing values of that parameter. What I want is to be ...
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By using dynamical programming, we can save intermediate steps for recursive relations, as in f[n_]:= f[n] = f[n-1] + f[n-2] However, this only stores ...
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This is a contrived example, but it gets the point across. I am looking to use the following as inputs: ...
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Here's an example to illustrate the issue I'm having. right = 8 - y; left = y^2 + 6; integrand = HoldForm[Evaluate[right]] - HoldForm[Evaluate[left]] (I ...