Questions about the use of built-in Mathematica functions, including pure functions.

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3
votes
0answers
63 views

Why is the evaluation of f different using rules and using arguments to it as a function? [closed]

I will provide all the code I used at the end of the question. I was trying to evaluate a function f with the following signature (which I'll give the details at ...
2
votes
1answer
86 views

creating a stacked function that returns the multi varibles

I'm a beginner in Mathematica with little programming background but I'm determined to learn this. I'm trying to make a function that calculates two variables r2 ...
2
votes
0answers
119 views

Input List of Images into a cloud deployed API function

I'm new to APIFunction and CloudDeploy, but essentially, here's my situation: I have a function (let's call it ...
2
votes
2answers
75 views

Replace All using a list

I have a more complicated case however a basic example is; ...
4
votes
2answers
245 views

Generate the Fibonacci sequence with Accumulate

Is there a way to generate the Fibonacci sequence with the Accumulate function?
0
votes
1answer
213 views
-2
votes
1answer
81 views

Why is my function returning 0 when when I try to give it arguments by replacement? [closed]

I tried running a function f with rules and calling it directly with arguments specified directly but the one with rules returns zero while the one with direct ...
3
votes
1answer
189 views

Derivative of conjugate multivariate function

I have a problem with Mathematica, taking the derivative of the conjugate of some function. I know that a similar question has been posed before here, but the solution did not work for multivariate ...
2
votes
1answer
201 views

Fitting one set of data with two function

I have a set of data (42 points): ...
8
votes
3answers
215 views

Adding colors to graphic objects made with the new function AnglePath

The MMA 10.2 help gives many examples of AnglePath lines of code but all of them are of the same color and I am quite at a loss to devise a method to add colors ...
0
votes
2answers
125 views

How does one define a function that takes vectors as arguments but also derivatives?

Summary: tldr; I just want to implement a version of the following mathematics function: $$ f(a) = c_1 e^{-(a - t_1)^2} + c_2 e^{-(a - t_2)^2} + c_3 e^{-(a - t_3)^2}$$ in mathematica, and be able ...
0
votes
1answer
35 views

How can I apply a matrix 2*2 to binary digits? [closed]

I want to apply a matrix 2*2 to a binary digits. For example, D and E are two matrices that they apply to a 1 and 0. D --> 1 & E --> 0 binary digits: (1011) --> D.E.D.D
1
vote
1answer
59 views

Using Get function to return a specific expression

I am trying to use Getto import data saved as a .nb document. The problem is Getevaluates all expressions but only returns the ...
2
votes
1answer
135 views

An error disappears?

I needed to define a table of functions. And I did it like this: ...
11
votes
1answer
124 views

Using Rules inside SequenceCases degrades Performance

Consider the following: SequenceCases[Range[10^4], {a_?PrimeQ, b_, c_?PrimeQ}]; // AbsoluteTiming {0.0058148, Null} If we now try to use a rule to transform ...
-1
votes
4answers
107 views

Converting an expression to function [duplicate]

I have the following problem. I current can automatically create the variable positionPayload, for instance: ...
3
votes
3answers
198 views
1
vote
1answer
72 views

I keep writing functions like this one: subtract[{a_, b_}] := Subtract[a, b] [duplicate]

(Edited to provide an example) Recently I have found myself writing silly functions like the following, which is just a new arity of Subtract in which the arguments are inside a list. ...
0
votes
1answer
60 views

Reverse of Apply on built-in functions [closed]

So if I have can use Apply and Or in combination: Or @@ {a, b, c, d} Out: a || b || c || d One could also use Or[a, b, c, ...
0
votes
1answer
79 views

Create a sum with the Do function and modules

I should define a function which sums up from k=0 to 100, with x=1; using the ...
6
votes
2answers
75 views

How to count the number of values in a discrete function?

I have a discrete function of an integer variable $n$ defined like this : ...
4
votes
1answer
118 views

Substitute a function's definition for its name

I'm having trouble with a function which is supposed to work on another function. Simplified version: ...
2
votes
2answers
92 views

Options for a function I define that can be passed to functions I call in the definition

I know, this is very close to Functions with Options and/or Function with custom Options and modified Options for built-in Symbols, but I don't get it. My function looks like this one: ...
0
votes
2answers
61 views

Function to list Collatz sequence doesn`t work [duplicate]

I am new to Mathematica and was trying to make a function that lists the Collatz sequence stating with a given number, but I can´t get it to work. Here is my function: ...
0
votes
1answer
82 views

Implementing Antilogarithm[b, x] and Cologarithm[b, x]

Mathematica functions for antilogarithm[b, x] and cologarithm[b, x] don't appear to exist, but I think they could be ...
18
votes
1answer
252 views

HistogramList is much Slower in 10.2 vs 10.1

While I was running a code I wrote using version 10.1, I noticed that in version 10.2 the running time of the same code was more than twice as long. After some digging, I figured out the culprit is ...
0
votes
2answers
64 views

Defining an array of functions with multiple indices and one variable [closed]

I have a function f of one variable x and a 4 x 3 array ...
1
vote
0answers
21 views

Use functions to call a named object [duplicate]

Now I have several interpolation functions called x30, x50, z30, z50...... I wish to write a function to call these function by inputing x or z and numbers automatically, and assign a argument x to ...
2
votes
2answers
112 views

Function with lazy and non-lazy arguments

Consider the function Z[entropy_, beta_] := Sum[E^(entropy[[i, 2]] - beta entropy[[i, 1]]) , {i, 1, Length[entropy]}] where entropy is a list of pairs (e.g. ...
16
votes
1answer
201 views

Undocumented fourth parameter of Collect; how long has it been there?

While tinkering with How to get a list of monomials of a polynomial without coefficients? on a whim I tried a fourth argument in Collect and found: ...
0
votes
1answer
101 views

Functions as objects [duplicate]

I have a very long program I'm trying to stuff express as a single function. (I'll include it at the bottom of my post.) My long-term goal is to trim out the file handling portion of this function, ...
2
votes
1answer
230 views

How to get numerical results from HeavisideTheta?

I have defined a table tab = {7.52521, 17.0083, 22.5678, 11.8707, 8.27799} and a function ...
2
votes
2answers
90 views

Analytic differential of an inverse transcendental function

I have the following function: $$ y(x)=\frac{Ax}{Bx^{1/4}\sinh{(\frac{Bx^{1/4}}{2})}}\left(\cosh{(\frac{Bx^{1/4}}{2})}-1 \right), $$ where $A=112.941$ and $B=18.6588$. I want to find the differential ...
0
votes
1answer
69 views

Module using for creating a table [closed]

I want to have a 4 tables with using of module. Unfortunately I don't know why doesn't it work ...
3
votes
2answers
376 views

Opposite of Alternatives

I was looking at this question (here) and I tried to find any thing gives the opposite of Alternatives. In other words, some pattern matching function that gives ...
3
votes
1answer
145 views

How can you get the area of a region from an image?

Suppose we have a square of side "L" m, How can I calculate the hatched area, if the corners of the square are centers of circles. It can be generalized to any region? edit: This is the result I ...
2
votes
1answer
55 views

Appending Delayed Evaluation

I have a function that need to be summed over all parameters given in a separate list. f[x_,y_,z_,n_,i_]:= (*Some function*); list={{n1,i1},{n2,i2},...}; I need ...
6
votes
2answers
348 views

Round vs. Floor vs. Ceiling for non-integers non-orders-of-magnitude

I understand that Round give the nearest even integer for cases where the number is between two integers, i.e. Round[2.5] = 2 ...
1
vote
1answer
156 views

DownValues when using Set and SetDelayed

It is known from several questions asked in SE that one of the basic differences between Set and SetDelayed is that the former ...
0
votes
1answer
62 views

Applying corresponding elements of a list to a list of functions

I found this post which applying a function to a list of functions and arguments. I thought I could change my code with a table to something more elegant. I am not wedded to the ...
2
votes
1answer
130 views

Use Map with multiple arguments over a nested list

I noticed there are a few similar questions to mine on here, but I couldn't figure out how to accomplish this mapping. I have sets of data I want to plot, which represent intensity and frames, and I ...
0
votes
3answers
103 views

Confusing “Part::pspec” and “Part::partw” following call to ParametricPlot3D

The problem I'm having is that the function definition given below continually gives me baffling error messages. I'm trying to turn a list of 3D points into a function that approximates a curve by ...
2
votes
2answers
222 views

Multiply pure function with scalar

Somtimes I still get lost in the Hold, HoldAll etc. functions of Mathematica. I want to scale a simple PDF function with a previously calculated variable e.g. ...
1
vote
0answers
57 views

Union sorting after ignoring some digits

I have a list with its bellow elements: {-0.7071067811865476, -0.7071067811865475, 0.7071067811865475, 0.7071067811865476} If I use Union, but there is no change. Because the numbers are different. ...
0
votes
1answer
56 views

Mapping Linear Model Fit Over An Arbitrary Number of sets

I have multiple sets of data, and I want to apply Linear Model Fit sequentially to each set of data. For example, below tstlst contains 3 data sets. Right now I ...
1
vote
0answers
50 views

How to test for a non--zero rational function? [duplicate]

I want to test if a rational function in one variable is identically zero. I was surprised that just writing f==0 doesn't do it. I wrote the following code: ...
0
votes
1answer
96 views

Plotting the tangent of a curve [duplicate]

I'm new to Mathematica and this is probably child's play for most people, but I wanted to know how to plot the tangent of the function below at the point e=1/4 : ...
0
votes
2answers
112 views

Examining the equations of a Differential Op Amp

I want to examine the equations of a differential Operational Amplifier, specifically I want to examine how the tolerances of the resistors affect the resulting differential gain and common mode ...
6
votes
1answer
127 views

Is there an elegant way of delaying evaluation of `A==B` when calling a function that uses this pattern

Suppose I wanted to define a number of functions that accepts expressions of the form: ...