Questions tagged [functional-style]
Questions about Mathematica's functional programming style, including the use of pure functions (Function[], #, &) and functions such as Map, Apply, Nest, and Through.
470
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Evaluating step functions
Please guys, how do I tell Mathematica to return f(a-b)= 1 if a=b and 0 otherwise?
This means that f(0)=1 and f(x)=0 for x>0.
- 31
4
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2
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130
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How to use functional iteration with changing function?
I recently came across this problem on reddit. The problem is supposed to be read like a snake, and the result of each succesive operation is sent to the next operation:
There are 9 blank boxes and ...
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2
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2
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How to implement this zip function? zip[g,{f[{a,b}],f[{c,d}]}] to f[{g[{a,c}],g[{b,d}]}]
I have a function that returns an expression in the form f[{a,b}], and I use this function twice and assemble the expression ...
- 431
4
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2
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Get cumulative sums in a list without using a for loop [closed]
I want a list of the kind list = {a,a+b,a+b+c} for list plotting. The quantities of the list come from a function. Let us say this is
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- 411
4
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1
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PatternTest in Function
This is probably trivial and already asked but I did not find it.
How to use PatternTest inside Function (...
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2
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1
answer
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Expression as parameter to function that evaluates it, best way to do it?
I need a function fSum that computes the angular sum for some expression, like this:
fSum[3 Sin[2 x], 0, 2 π]
Or from a predefined function, like this:
f[x] = 2 Sin[3 x];
fSum[f, 0, 2 π]
Or plots it ...
- 101
0
votes
2
answers
62
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Problem with $ sign in temporary function parameter
I am having a problem with $ sign in the name of a parameter to a temporary function. The functions I have should compute the angular sum (or turning angle) for some expression generated by function <...
- 101
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1
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Quickly processing long lists using SequencePosition
Overview
SequencePosition does exactly what I need; however, it seems to be very slow for long lists. Is there an input option that would allow it to process faster? Or, perhaps an alternative ...
- 1,069
4
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3
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656
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Concise version of MATLAB code
Please see this MATLAB code:
k=0:8;
wk=2 * pi * k/17;
ak=double(wk<0.5*pi)
It generates ak with such a simple expression. To ...
- 889
5
votes
1
answer
81
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Undocumented behavior of Fold for arbitrary heads [closed]
Edit: I'm apparently blind. Sorry! And thanks to those who answered anyway.
Apologies in advance if this is sort of a nitpicky question, but I'm generally very paranoid that I don't fully understand ...
- 111
4
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1
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How to shorten the plotting code using slots and table? [closed]
Background Information
I have the following Mathematica code:
...
- 2,433
0
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1
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59
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How to evaluate expressions which involve derivatives and evaluations of functions in a specific case, via a condition?
I have an expression involving the derivative of an arbitrary function r_0
c0 = Derivative[1][Subscript[r, 0]]
Later I must replace r_0 by several specific ...
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6
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4
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428
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Subdivide a sequence
Yesterday I couldn't solve a problem which seemed to be rather simple. I tried RepleaceRepeated, SequenceReplace and similar ...
- 81.5k
0
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1
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91
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How can I apply Residue in a functional-style way? [closed]
Let me suppose that I have got some expression, for example
f_{1}(x)+f_{2}(x)
and also a list of a form:
{1,2}
How can I apply ...
- 69
6
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8
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405
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Removing duplicates between sublists
I want do delete from each sublist those elements which are contained in one or more of the other sublists. The surviving elements must maintain their original order of appearance.
...
- 81.5k