Questions tagged [uniroot]
33 questions
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How to find the input of a function given we have the output
I have a function that is calcualting a profitmargin (PM) given a principal(P).
PMfunction<- function(P,InterestRate,Expenses){
...
There are quite a lot of calcualtions in the middle that come off a table and it's irrelevant
...
return(PM)
}
I now…
Fizboy
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0
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Error in integrate : evaluation of function gave a result of wrong length after Vectorize
I am trying to simulate survival data from a Weibull PH model with a time varying covariate.
I wrote a function invS that integrates the hazard function containing the time-varying component.
Then I used the uniroot function with invS as a function…
Faithhhhhh
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0
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2 answers
Update value in function using uniroot
Just some smaller changes which do not need to be considered.
Kalle Blomkvist
- 41
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1 answer
how to predict x given y for nls model?
I am using the nls SSlogis function in R to make a model expressing water absorption in a plant, where y=water absorption (g per m^2), and x=minutes in water. For a given y value (in this case max water absorption), I would like to solve for x (the…
treee
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1 answer
How can I combine uniroot and lapp/overlay function from terra package to perform raster calculation?
I am trying to lapp from terra package to solve an equation with raster cells and uniroot function. I am stuck on how to get the final raster output from combining lapp and uniroot functions.
I would be thankful for any kind of…
Floyid Nicolas
- 29
- 5
0
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1 answer
Solving a single variable equation in R using unitroot
I have a complicated equation for which I have written the code as follows:
sigma = 1.336449027;
f_t = 0.500185113;
alpha = 0.364; #elasticity of capital
beta = 0.115; #elasticity of labor
R = 3.131696599;
chi = 0.5;
M = log(1056);
sigma =…
riskiem
- 187
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0
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1 answer
Why can't I use uniroot with plot?
I am working on code that uses the uniroot function to approximate the root of an equation. I am trying to plot the behaviour of the function being passed through uniroot as the value of a free variable changes:
library(Deriv)
f1 <- function(s) {
…
Tim C
- 3
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0
votes
1 answer
Uniroot solution two equatations
I posted similar question a few days later, but now I have more complex problem.
I have this dataset
product = data.frame(length = c(100, 200, 300, 400), qty = c(1, 2, 1, 3))
And price is defined by this equation (product[["length"]] * old_const *…
onhalu
- 735
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0
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0 answers
RuntimeWarning: invalid value encountered in power scipy.optimize root
basically I am trying to reproduce an example from a website because I want to find the equivalent to the R uniroot for python. I found a blog entry (https://waterprogramming.wordpress.com/2016/08/18/root-finding-in-matlab-r-python-and-c/) where the…
scriptgirl_3000
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1 answer
Why is uniroot.all throwing unused variable error when root function has multiple arguments?
Once in a blue moon I need to use the lovely uniroot.all function from the rootSolve package to find the root(s) of a function with multiple arguments. Every time I do this I run into a bunch of snags which I eventually resolve, but then forget how…
ben
- 787
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0
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1 answer
How to avoid uniroot error that stops the loop
I am running uniroot function in the loop, but hit an error and the code stopped. The code is as below;
func <-function(f) -a*b/c*0.5*d*e^2 + (d/f-1)*g*sin(h*(pi/180))-i
dat <- data.frame(a = c(0.99,0.99,0.99),
b =…
imtaiky
- 191
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0
votes
1 answer
How can I avoid uniroot error that stops the loop?
I am running uniroot function in the loop, but hit an error and the code stopped. The code is as below;
func <-function(f) -a*b/c*0.5*d*e^2 + (d/f-1)*g*sin(h*(pi/180))-i
dat <- data.frame(a = c(0.99,0.99,0.99),
b =…
imtaiky
- 191
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- 12
0
votes
1 answer
R function "uniroot": get some mistake
FX <- function(x)(3/4)*(1-x^2)
M <- 5000
X2 <- rep(NA,M)
for (i in 1:M) {
U2 <- runif(1)
fct <- function(x)FX(x)-U2
X2[i] <- uniroot(fct,c(-1,1))$root
}
I have tried to do this R-code but I every time I get a mistake saying:
Error in…
Lifeni
- 159
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0
votes
1 answer
Uniroot Upper and Lower values in R
I trying to find the solution of the following using uniroot() in R.
library(rootSolve)
set.seed(2)
y=rgamma(10,5,2)
myfun=function(y,t)as.numeric(integrate(function(x){ ((x^4) * exp(-x/2))/768 },0,upper=2)[1])-t
myfun(y,…
score324
- 687
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0
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0 answers
error in uniroot() in R, f.lower = f(lower) is NA + actual example
here is my code,
a3<- c(-1141591.0, -1192686.3, -402424.1, -418201.6, -439137.0, -654150.5, -670148.4 , -696922.9, -719566.3,
-766338.7, -794186.4 ,-812940.5, -835722.0, -856374.3)
a2<- c(271925.56, 284085.61, 95976.92, …
Mathica
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