Questions tagged [expression-manipulation]
How to manipulate expressions structurally, not necessarily complying with the rules of algebra.
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Ignore higher order terms in an expression
I am trying to ignore terms that are higher order (third or more) in an expression. For example, for the input function:
$$f_{in}= \alpha\beta + \alpha^2 + \beta^2 + \alpha\beta^2/2 +
\alpha^2 \beta $...
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Putting a polynomial into a multilinear form
Consider the polynomials in $x$ with positive-integer parameters $a,b,c$
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Breaking multiple summations of terms in single term summations
I have a question which is a follow-up of a previous one: Break summation of terms in summations of each term.
I noticed that using Distribute on a summation (...
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Break summation of terms in summations of each term
I am trying to break the summation over two terms in two summations for each term, that is:
From \begin{align}\sum\limits_{l}^{L}a_{l}^2(-t_{l}t_{x} + t_{l}^2t_{x})&\end{align} to \begin{align}\...
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Is there an easy way to understand how to manipulate summations?
I'm working in a very very long calculation that could be done by hand but it might be tedious. Moreover, when doing by hand that amount of calculations I'm subject to errors, of course. Then I ...
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Why is Mathematica not simplifying this matrix?
I have trouble simplifying the following matrix
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- 143
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Using patterns to replace the head of certain expressions [duplicate]
I would like to match things like
Times[Cycles[_],Cycles[_],..]
and replace them with
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Simplifying expression efficiently
I have the following expression that I want to simplify to have an optimized/nice output.
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How to remove only circular refs in Language`ExpressionStore
Expressions are not garbage collected if there are references to them stored in the expression store. I use the following internal functions:
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Speeding up the output of DSolveChangeVariables
I am trying to change the variable in a differential equation using the above mentioned function. This is what I did:
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How to find the argument dependance of an expression
Consider expressions such as
X := f[n[1]][n[3]] g[n[7], n[1923]]
I would like to construct a function that returns the list of $n$'s on which $X$ depends. I know ...
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Finding constant term in product expression
I've an expression which is product of 20 or more factors of polynomial, something like $$\left(1-\frac{pq}{z^i}\right)(1+pq z^j+z^k)$$ and I want to find coefficient of $z^0$. SeriesCoefficient works ...
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How to group terms of a Fourier series properly?
I want to organize my expressions as a fourier series of sin and cos.
That is, I want them to be of the form $$a_0 + a_1 \cos[ w t] + b_1 \sin[ w t] + a_2 \cos[2 w t] + b_2 \sin[2 w t] + ... $$
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Mapping function across its arguments
Is there a more elegant way to do the following? (The code should be f-less and replacement-less)
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FullSimplify exponential gives zero [duplicate]
gs[x_, h_, c_, w_] := h*Exp[-Log[2]*(x - c)^2/w^2];
gs[x, 0.343131084805, 118.276987081, 4.0035196987]
gives
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