All Questions
11
questions
1
vote
2
answers
106
views
Symbolic derivative of transposition
I have an expression:
expr = Transpose[x]+Transpose[f[x]]+Transpose[x+f[x]]
I want to differentiate this expression and desired result looks like this:
...
- 2,444
1
vote
0
answers
37
views
Replace subexpression with variable in result from Laplace transform
I'd like to clean up the result I obtained from an inverse Laplace transform:
First of all, I'd like to replace the square root expressions in the hyperbolic function arguments (part encircled in ...
- 11
2
votes
2
answers
89
views
Formal substitution of exponential factors in an expression
Assume that we have some complex algebraic expression, like
Exp[(a t + b s)/w] ( t Exp[ q t] w + q Exp[q s] Exp[-2 s] + a^2 Exp[3 s] + s t + 1 )
Now, this is just ...
- 143
0
votes
0
answers
96
views
How to rearrange terms in an expression to a particular form (e.g. A/w-> A*(1/w)
I have a huge expression for which the numerators are a big mess, involving numbers, variables, formal sums and unevaluted function, let's call the numerators Ai, with i=1,2,...n
This "beast"...
- 1
0
votes
0
answers
68
views
How can I use a replacement rule as part of a simplification?
I am using Mathematica to symbolically calculate the likelihood for a simple linear regression model. As part of this I want to substitute
...
user57885
2
votes
1
answer
72
views
How to get the result in terms of a previously defined expression?
Say I have a vector
X[n_] := Table[Subscript[x, i], {i, 1, n}]
and a matrix of connections:
...
- 214
0
votes
3
answers
474
views
How to simplify an expression by substitution?
Sometime Solve and DSolve give a finial form of the solution, which is fine in may applications. However, in some cases, one may ...
- 1,229
1
vote
3
answers
180
views
Elimination of terms not containing at least one variable from a set
I have an expression with each term therein either containing at least one $n_i \in \left\{ n_1 , n_2 \dots , n_{5} \right\}$ or no $n_i$ at all. I would like to easily eliminate all the terms that ...
- 510
0
votes
1
answer
335
views
Solving a trigonometric equation for all $x$ using constant coefficients
I want to find the coefficients $a$, $b$, $c$, etc. that make an equation like $a+bx=x$ true for all $x$, but for trigonometric functions of $x$. For example
...
- 341
2
votes
2
answers
115
views
Trouble simplifying using Replace
I have the following expression:
w.a.b.r+w.c.d.r
I want to get:
w.(a.b+c.d).r
So far I used ReplaceRepeated:
...
- 851
0
votes
1
answer
166
views
How to convert the expression '{a->a0, b->b0}' to the expression 'a=a0; b=b0'? [duplicate]
How to convert the expression '{a->a0, b->b0}' to the expression 'a=a0; b=b0'?
I think this is a common question and do not know if someone has asked it before. Any help or suggestion will be ...
- 1,145