July 2014 - Comp-phys-alps-users

Inconsistent comment in generate_spline_matrix in the DMFT folder
by Kuangshing Chen 22 Jul '15

22 Jul '15

Hi, The function generate_spline_matrix in fouriertransform.C in the dmft folder shows the comments as follows: // A is the matrix whose inverse defines spline_matrix // // 6 6 // 1 4 1 // 1 4 1 // A = ... // // 1 4 1 // -2 0 0 2 However, the following codes, dense_matrix A = 4*dt/6.*boost::numeric::ublas::identity_matrix<double>(Np1); for (int i=1; i<Np1-1; i++) { A(i,i-1) = dt/6.; A(i,i+1) = dt/6.; } A(0,0) = 1.; A(0, Np1-1) = 1.; A(Np1-1, 0) = -2.*dt/6.; A(Np1-1, 1) = -1.*dt/6.; A(Np1-1, Np1-2) = 1*dt/6.; A(Np1-1, Np1-1) = 2*dt/6.; the red lines will make the matrix looks like // 6 6 // 1 4 1 // 1 4 1 // A = ... // // 1 4 1 // -2 *-1* *1* 2 Is the comment correct or the code correct? Any reference for this algorithm? Thank you, Kuang-Shing Chen

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Help regarding sparse diagonalization
by Sriluckshmy Viswanathan 15 Aug '14

15 Aug '14

Hi, I am writing a code for the computing gap in kitaev-heisenberg model on the honeycomb lattice using sparse diagonalization. When the coupling for the kitaev term is zero the model patch that I wrote should match the model that is inbuilt. But that doesnt happen. I may have made a mistake in the model patch which is as follows. <HAMILTONIAN name="kitaev heisenberg"> <PARAMETER name="J" default="1"/> <PARAMETER name="Jz" default="0"/> <PARAMETER name="Jx" default="0"/> <PARAMETER name="Jy" default="0"/> <BASIS ref="spin"/> <BONDTERM source = "i" target="j"> J*Sz(i)*Sz(j) +J*exchange_xy(i,j) </BONDTERM> <BONDTERM type="0" source="i" target="j"> Jz*Sz(i)*Sz(j) + J*Sz(i)*Sz(j) +J*exchange_xy(i,j) </BONDTERM> <BONDTERM type="1" source="i" target="j"> Jx*Sx(i)*Sx(j) + J*Sz(i)*Sz(j) +J*exchange_xy(i,j) </BONDTERM> <BONDTERM type="2" source="i" target="j"> Jy*Sy(i)*Sy(j) + J*Sz(i)*Sz(j) +J*exchange_xy(i,j) </BONDTERM> </HAMILTONIAN> I have also attached the output that I got in dat format. Could you please help me with this problem? Sriluckshmy

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Building alps from source
by Niraj Ghimire 08 Aug '14

08 Aug '14

Dear alps users, I have been trying to build alps from source on Fedora 20 and I am having issues. I am new to alps and Linux OS itself, so I am spending too much time. I followed the instructions on "Get dependent libraries and tools on Fedora 20" and that was easy to understand and work out. Now I am on "Build ALPS". Either the instructions on "Build ALPS" are not sufficient for a Linux beginner like me or I am not being able to follow them. Please provide me with detailed instructions/guidelines or anything that helps, I will truly appreciate it. Thanks, Niraj

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instalation problem
by Hocine Ahmed 29 Jul '14

29 Jul '14

Hello I installed all debian library to install ALPS and I created a build directory. when I run make , I have this messages make[2]: *** No rule to make target « alps2/alps/src/alps/hdf5/archive.cpp », required for « src/alps/CMakeFiles/alps.dir/hdf5/archive.cpp.o ». stop. make[1]: *** [src/alps/CMakeFiles/alps.dir/all] Erreur 2 make: *** [all] Erreur 2 thank you to answer me Best regards ------------------------------------------------------------------------- Mr Hocine Ahmed LABORATORY FOR THEORETICAL PHYSICS AND MATERIAL PHYSICS HASSIBA BENBOUALI UNIVERSITY BP. 151, 02000 CHLEF, ALGERIA Tel:+213790974582 ; mail: ah.hocine(a)univ-chlef.dz

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Question on multi-orbital PAM simulation
by Žiga Osolin 29 Jul '14

29 Jul '14

Dear ALPS community, I am trying to check if DMFT(QMC) calculations are consistent with my DMFT(NRG) calculations. I am working on Kondo lattice model (KLM), and I guess to simulate it with QMC, I have to consider PAM with correct parameters that translate to the KLM limit; the repulsion of f states should be high, U_f=8, on site energy e_f = -4 and hopping on the c states for example t=0.8. There is also spin-spin interaction J in KLM, here just the interaction between c and f orbitals, in PAM just V. Correct me if something is wrong please: a) To simulate such lattice, I should set 4 flavors. The U matrix should look like (c_up c_down, f_up, f_down): [0 0 V 0 ] [0 0 0 V ] [V 0 eps_f 2*eps_f + U_f] [0 V 2*eps_f + U_f eps_f] How do I set such a matrix in parameters? (U1 = U_f, ...) b) The hopping terms are t0=0.8 and t1=0 ? (ALPS automatically assumes 0, 1 belong to first site, 2, 3 to the second?) c) I need antiferromagnetic solutions; is it sufficient to calculate using ANTIFERROMAGNET=1 or should I use some sort of cluster schemes to really get the correct spectral function? (I using a cluster scheme as simple as setting SITES=2 for example?) d) I need to simulate the model in a magnetic field, is this possible in QMC? Is magnetic field possible in x direction (the spin symmetry is broken here, there is no S_z symmetry anymore)? The solution when magnetic field is applied also creates AF magnetization in x direction, is it possible to break symmetry in a way to achieve this (small field in x direction, get it to 0 ...) Best regards, Ziga

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dimerized chain
by Stone, Matthew B. 26 Jul '14

26 Jul '14

ALPS community, I am interested in calculating the states and the spin-spin correlation functions for a dimerized chain. This type of structure is sometimes called an alternating chain. It consists of spins coupled along one-dimension with alternating strong and weak Heisenberg exchange parameters: J0---J1---J0---J1---J0--- Using the tutorials and the ALPS website, I have assembled what I think are the correct UNITCELL and LATTICEGRAPH (see end of message). Q1: Is there a way to check this definition visually? The wiki suggests the command printgraph parameter_file Q2: does the predefined 'MODEL' "spin" account for J0 and J1 exchange? Q3: Can 'S' also be a conserved quantum number. Thanks for your assistance. Matt Stone parms = [{ 'LATTICE' : "dimechain", 'LATTICE_LIBRARY' : "latticeCN.xml", 'MODEL' : "spin", 'local_S' : 0.5, 'J0' : 1, 'J1' : 0.125, 'L' : 6, 'CONSERVED_QUANTUMNUMBERS' : 'Sz', 'MEASURE_CORRELATIONS[Diagonal spin correlations]=' : 'Sz', 'MEASURE_CORRELATIONS[Offdiagonal_spin_correlations1]' : 'Splus:Sminus', 'MEASURE_CORRELATIONS[Offdiagonal_spin_correlations2]' : 'Sminus:Splus, 'D' : 0.0, 'h' : 0.0, }] <UNITCELL name="anisotropic1d" dimension="1"> <VERTEX/> <EDGE type="0"> <SOURCE vertex="1" offset="0"/> <TARGET vertex="1" offset="0.5"/> </EDGE> <EDGE type="1"> <SOURCE vertex="1" offset="0.5"/> <TARGET vertex="1" offset="1"/> </EDGE> </UNITCELL> <LATTICEGRAPH name = "dimechain" vt_name="dimechainLattice"> <FINITELATTICE> <LATTICE ref="chain lattice"/> <EXTENT dimension="1" size="L"/> <BOUNDARY dimension="1" type="periodic"/> </FINITELATTICE> <UNITCELL ref="anisotropic1d"/> </LATTICEGRAPH>  <LATTICE name="chain lattice" dimension="1"> <PARAMETER name="a" default="1"/> <BASIS><VECTOR>a</VECTOR></BASIS> <RECIPROCALBASIS><VECTOR>2*pi/a</VECTOR></RECIPROCALBASIS> </LATTICE>

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Re: [ALPS-users] Comp-phys-alps-users Digest, Vol 100, Issue 5
by emmanuel enukpere 24 Jul '14

24 Jul '14

Dear Prof. Troyer, There was no reply to problem of not being able to invoke vispython from the Cygwin command line: ENUKPERE@ENUKPERE-PC /cygdrive/c/cygwin/ALPS/bin$ vispython -bash: vispython: command not found How do I proceed? Thanks for your untiring effort in answering all the various posts. On Saturday, July 19, 2014 11:00 AM, "comp-phys-alps-users-request(a)lists.phys.ethz.ch" <comp-phys-alps-users-request(a)lists.phys.ethz.ch> wrote: Send Comp-phys-alps-users mailing list submissions to comp-phys-alps-users(a)lists.phys.ethz.ch To subscribe or unsubscribe via the World Wide Web, visit https://lists.phys.ethz.ch/listinfo/comp-phys-alps-users or, via email, send a message with subject or body 'help' to comp-phys-alps-users-request(a)lists.phys.ethz.ch You can reach the person managing the list at comp-phys-alps-users-owner(a)lists.phys.ethz.ch When replying, please edit your Subject line so it is more specific than "Re: Contents of Comp-phys-alps-users digest..." Today's Topics: 1. Re: Building alps from source (Niraj Ghimire) 2. INSTALLATION OF ALPS IN WINDOWS 7 32-BIT SYSTEM (emmanuel enukpere) ---------------------------------------------------------------------- Message: 1 Date: Fri, 18 Jul 2014 15:04:36 -0400 From: Niraj Ghimire <niraj.ghimire(a)gmail.com> To: comp-phys-alps-users(a)lists.phys.ethz.ch Subject: Re: [ALPS-users] Building alps from source Message-ID: <CACMdJOWTHJYg+y9E9__io4Ro+ESk9=HXuvwzm8n2azFRYUYowA(a)mail.gmail.com> Content-Type: text/plain; charset="utf-8" Hi Dr. Troyer, I am stuck at the "Build ALPS section". Listed below are the instructions I followed along with what I actually did: Download a source package of ALPS: I downloaded alps-2.1.1-r6176-src.tar.gz <http://alps.comp-phys.org/static/software/releases/alps-2.1.1-r6176-src.tar…> (I was wondering if downloading alps-2.1.1-r6176-src-with-boost.tar.gz <http://alps.comp-phys.org/static/software/releases/alps-2.1.1-r6176-src-wit…> would be better). Create a build directory and execute cmake giving the path to the alps and to the boost directory: I unzipped the source package and tried using $ cmake -DCMAKE_INSTALL_PREFIX=/path/to/install/directory /path/to/alps/directory I don't know if I really understood this command line. But when I used it, I the error message "Cmake Error: The source directory does not appear to contain Cmakelists.txt" Thanks, Niraj On Wed, Jul 16, 2014 at 11:29 AM, Matthias Troyer <troyer(a)phys.ethz.ch> wrote: > Hi, > > You need to tell us more about where you get stuck if you want to receive > help. > > Matthias Troyer > > > > > > On Jul 16, 2014, at 7:44, Niraj Ghimire <niraj.ghimire(a)gmail.com> wrote: > > > > Dear alps users, > > I have been trying to build alps from source on Fedora 20 and I > am having issues. I am new to alps and Linux OS itself, so I am spending > too much time. I followed the instructions on "Get dependent libraries and > tools on Fedora 20" and that was easy to understand and work out. Now I am > on "Build ALPS". Either the instructions on "Build ALPS" are not sufficient > for a Linux beginner like me or I am not being able to follow them. Please > provide me with detailed instructions/guidelines or anything that helps, I > will truly appreciate it. > > > > Thanks, > > Niraj >

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INSTALLATION OF ALPS IN WINDOWS 7 32-BIT SYSTEM
by emmanuel enukpere 22 Jul '14

22 Jul '14

I have been trying to install ALPS in Cygwin in my Windows 7 32-bit system. After installing ALPS I got to the point where according to the instructions: "If, on the other hand, you install the binary ALPS package for MacOS or Windows you will need to download and install also Vistrails since the ALPS packages were built against the Python interpreter shipped with Vistrails. To do so call vispython " I tried to call as shown below with no success: ENUKPERE@ENUKPERE-PC /cygdrive/c/cygwin/ALPS$ vispython -bash: vispython: command not found I then tried to manually look for vispython in the ALPS folder and found it in ALPS/bin ENUKPERE@ENUKPERE-PC /cygdrive/c/cygwin/ALPS/bin$ vispython -bash: vispython: command not found When I issued the command vispython the system said command not found. When I double clicked on vispython it dpened a new command window C:\Windows\system32\cmd.exe Sirs, I do not know what I have done wrong. Please me resolve this issue in the installation of ALPS. I am in dire as my professor is waiting impatiently for me/ Thanks ENUKPERE.

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Measuring the average value of a bond operator
by pradeep thakur 18 Jul '14

18 Jul '14

Dear All, I'm running the dmrg application and am wanting to measure the average of a bond-operator. How to measure the average value of an operator that contains non-local terms like S(i)plus*S(i+1)minus or S(i)plus*S(i+2)minus? Also is it possible to measure the value of such operators separately for each bond, the way we measure "local" operators for each site? http://alps.comp-phys.org/mediawiki/index.php/Tutorials:MeasureHOWTO This page says that it is not possible to do this, as of now. Have there been any recent developments to the contrary? Thank you for your time. Really grateful for any clarification provided. regards, Pradeep Thakur, University of Pune, Pune, INDIA.

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CT-QMC
by tesfaye mamuye 07 Jul '14

07 Jul '14

Dear alps developers and users I'm using the recent version package alps-2.2.b3-r7462 of CI-QMC (HYB expansion), alpspython together Python interface of the solver. I'm running on my laptop. I'm working on single-site DMFT. I need to know the recommended values of parameters N_MEAS, SEED, and MAX_TIME. I saw the tutorials but the Values are different in the two tutorials. Thank you

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