# Tag Info

Accepted

### Imposing special structure on Positive Semi-Definite matrix

The whole point is that you do NOT include the constraint $U = uu^T$ . That constraint is non-convex. Instead you include the constraint that $Z_j$ is (positive) semi-definite. This constraint is ...
• 2,232
Accepted

### Why am I getting this DCPError when my matrix is PSD?

Because the matrix KK is not PSD. It has minimum eigenvalue of -1. It is indefinite. Perhaps you are under the misapprehension that a symmetric matrix with all elements positive is PSD. As this ...
• 2,232

### What algorithm does CVXPY actually use to solve semidefinite programs with the constraints of the form $\sum\limits_i E_iXE_i^T \succ B$?

I assume your question is "which optimizer did cvxpy choose for my problem", as cvxpy can use a number of optimizers that it selects based on the problem, and indeed the output doesn't ...
• 131
Accepted

• 55.8k
1 vote
Accepted

### Why is CVXPY throwing a DCP error with cp.sqrt but no error with cp.norm

Based on your experience, one of (ignoring the subscripts) h or p must be a variable. Therefore ...
• 2,232
1 vote
Accepted

### Norm constraint in CVXPY

CVXPY's norm atom won't accept a raw Python list as an argument; you need to pass it a CVXPY expression. Stack the list of scalars into a vector using the hstack atom, like so: ...
1 vote
Accepted

### Why am I getting this DCPError?

cvxpy's rules for disciplined convex programming are listed here. Notably, it states that: The DCP rules require that the problem objective have one of two forms: Minimize(convex) ...
• 3,971
1 vote

### Defining a soft constraint in cvxpy

EDIT: Intermediate solution ...

Only top scored, non community-wiki answers of a minimum length are eligible