In which case does the transformation matrices T1, T2 always exist?

Suppose each element of matrix A is the linear presentation of n independent variables. And matrix B is the formed by such n variables. The question is, does there always exist T1,T2 that enable...

08 September 2019 195 7 View

How to obtain all the possible T of the folowing matrix equation via matlab?

Equation: [a b 0;0 0 c]*T=[a b 0;0 c c]. Suppose a b c are known varibles. T is a matrix. When I use matlab to solve this equation, there comes a warning "The system is rank-deficient. Solution...

03 April 2019 2,728 11 View

Under what condition will square matrixs follow the commutative Law of multiplication?

To make two square matrixs A and B satisfy the commutative law of multiplication, say, AB=BA, at least one of the following conditions is required: Condition 1: A=B. Condition 2: A=kI or B=kI....

02 March 2019 7,336 31 View

Is there an analytical solution to this kind of second order differential equation?

It's very similar to modified Bessel function. But it's second coefficient is 2 rather than 1. r^2dX^2(r)/dr^2+2rdX(r)/dr-(r^2+p^2)X(r)=0 , p is a known quantity.

01 February 2019 7,543 3 View

Is it practical to apply learning algorithm to real time control systems?

Learning algorithms can enhance the adaptive ability of the control system, but they tend to require iterative calculation, which may influence the real time performance .

10 November 2018 7,038 3 View

Is there an artificial intelligent technology using no machine learning algorithms?

As the title suggests.

09 October 2018 3,277 0 View

What is the right way to learn modern control theory?

The complicated mathematical formulas and theories is too abstract and tedious for me. How to develop the interest in modern control theories?

08 September 2018 8,542 4 View

Why all the matrices have to be rectangular?

Why not arrange the matrix elements in triangular lattice, or other other topologies?

08 September 2018 3,898 6 View

What's the relationship between machine learning, statistics and optimization?

It will be great if there is an example to show the differences of the three fields.

08 September 2018 6,125 1 View

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

MD MOE RMSD

How to calculate the RMSD values for a MD simulation using MOE?

07 August 2021 0 0 View

MGL tools

20 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

fatal error

When I tried to energy minimization my system, I got fatal error as below. Fatal error: Atomtype opls_116 not found Although I've already added this line: ; include water #include "oplsaa.ff/spc.itp" to [molecultype] directive in my topology.

16 June 2021 0 0 View

i have some problem with chtMultiRegionSimpleFoam

--> FOAM FATAL ERROR: Maximum number of iterations exceeded From function Foam::scalar Foam::species::thermo::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar) const) const [with Thermo = Foam::hConstThermo >; Type = Foam::sensibleEnthalpy; Foam::scalar = double; Foam::species::thermo = Foam::species::thermo >, Foam::sensibleEnthalpy>] in file /home/ubuntu/OpenFOAM/OpenFOAM-4.1/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 66. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::calculate() at ??:? #3 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::correct() at ??:? #4 ? at ??:? #5 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #6 ? at ??:?

24 March 2021 0 0 View