FloatingPointError: The system is too ill-conditioned for this solver. The system is too ill-conditioned for this solver - graph

I am trying to reproduce a GitHub repo. I have normalized data using minmaxscaler(). However, when I use graph lasso to get the skeleton of my data using:
skeleton = glasso.predict(df)
I face the following error:
FloatingPointError: The system is too ill-conditioned for this solver. The system is too ill-conditioned for this solver. What does this mean? How to resolve this issue?

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Error performing sensitivity analysis on binary integer programming model using LpSolveAPI package in R

I have a basic binary linear programming model with twenty-five constraints and 416 variables. I create the model and solve for an optimal solution, using the LpSolveAPI package, with no problem. However, when I try to run the package's sensitivity analysis functions I receive this error:
'''Error in get.sensitivity.obj(ff.lp) : OPTIMAL solution'''
If the function is run before the model is solved then this error is given:
'''Error in get.sensitivity.obj(ff.lp) : Model has not been optimized'''
There is no reason the solution being optimal should prevent sensitivity analysis. I don't understand what this error is telling me and I can't find the source code of the function to see what conditions are producing this error message.
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Specify solver in CVXR

I am new to the package CVXR. I am using it to do the convex optimization within each iteration of EM algorithms. Everything is fine at first but after 38 iterations, I have an error:
Error in valuesById(object, results_dict, sym_data, solver) :
Solver failed. Try another.
I am not sure why the solver works fine at first but then fails to work later. I looked up the manual about how to change the solver but could not find the answer. I am also curious about whether we can specify learning step size in CVXR. Really appreciate any help
The list of installed solvers in CVXR you can get with
installed_solvers()
In my case that is:
# "ECOS" "ECOS_BB" "SCS"
You can change the one that is used just using argument solver, e.g. to change from the default ECOS to SCS:
result <- solve(prob, solver="SCS")
I think the developers are planning to support other solvers in the future, e.g. gurobi...

Configuring SOCP solver in 'R'

I am trying to use the Rsocp package in R to solve a linear optimization problem with quadratic constraints. Much like in R - fPortfolio - Error in eqsumW[2, -1] : subscript out of bounds
More specifically I am attempting to maximize an expected return given a target risk parameter and portfolio/position limits.
install.packages("Rsocp", repos="http://R-Forge.R-project.org")
install.packages("fPortfolio")
require(fPortfolio)
require(Rsocp)
I run
lppData=100*LPP2005.RET[,1:6]
maxRetSpec=portfolioSpec()
setTargetRisk(maxRetSpec)=0.07
groupConstraints <- c("minsumW[1:6]=-.75",
"maxsumW[1:6]=1.75")
boxConstraints <- c("minW[1:6]=-1",
"maxW[1:6]=1")
bgConstraints <- c(groupConstraints, boxConstraints)
setSolver(maxRetSpec)="solveRsocp"
efficientPortfolio(data=lppData, spec=maxRetSpec, constraints=bgConstraints)
and get the following error...
Error in eqsumW[2, -1] : subscript out of bounds
It is my understand that Rsocp is a second order cone solver designed specifically for this purpose. Having gone through several different stackexchange forums it seems there are several people who have encountered this problem with unsatisfactory solutions. I was wondering if anyone has had success using the Rsocp solver that could give me a hand working through this error? Or alternatively can someone point me towards an 'R' solver that can handle this type of optimization problem?

How to deal with NAN warning message in poweRlaw package in R?

I am using poweRlaw package to fit distribution as described by Gillespie , but I got this warning messages which is given in attach and I am blocked can't go on?
What should I do for continuing with the procedure?
How to deal with NAN warning message in poweRlaw package in R?
I suspect you have numerical instability. This usually means that the lognormal isn't suitbale. However, without a reproducible example it's not possible to tell. Create an issue at https://github.com/csgillespie/powerlaw with a data set that can be used to reproduce the problem.

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