Dear Henry,
Here I will only reply to the measurements question, since you already posted the installation problem to the ALPS-Users mailing list, which is actually the right place for it.
You are lucky that you just want to measure something very similar to what a colleague of us is doing.
In general, special and models and measurements can be implemented in the XML description of the model library, which is documented on the ALPS website. models: https://alps.comp-phys.org/mediawiki/index.php/Tutorials:ModelHOWTO measurements: https://alps.comp-phys.org/mediawiki/index.php/Tutorials:MeasureHOWTO
As you find in the measurement tutorials, they the actual implementation may change a bit from application to application. What follows is specific to the MPS codes. You find more in our paper and in the online documentation of the input parameters http://alps.comp-phys.org/static/mps_doc/parameters.html
1) Structure factor We don’t support is directly in the MPS codes, but you can measure the density-density correlation function and then do the Fourier transform yourself. MEASURE_CORRELATIONS[Density correlation] = “n:n” or (only for MPS codes) if you ok having only <Psi | n_i n_j | Psi> with i<j: MEASURE_HALF_CORRELATIONS[Density correlation] = “n:n”
2) String operator You need to define the corresponding operator in you basis, e.g. (highlighted in red are the new parts) <SITEBASIS name="boson"> <PARAMETER name="Nmax" default="infinity"/> <PARAMETER name="rho" /> <QUANTUMNUMBER name="N" min="0" max="Nmax"/> <OPERATOR name="bdag" matrixelement="sqrt(N+1)"> <CHANGE quantumnumber="N" change="1"/> </OPERATOR> <OPERATOR name="b" matrixelement="sqrt(N)"> <CHANGE quantumnumber="N" change="-1"/> </OPERATOR> <OPERATOR name="n" matrixelement="N"/> <OPERATOR name="dn" matrixelement="rho-N" /> <OPERATOR name="String" matrixelement="cos(pi*(rho-N))" /> </SITEBASIS>
You can then use the MEASURE_LOCAL_AT measurement type (see documentation). Example in the parameters Nmax=4 rho=2 MEASURE_LOCAL_AT[String - 2] = “dn:String:String:dn|(1,2,3,4),(2,3,4,5),(3,4,5,6)" MEASURE_LOCAL_AT[String - 4] = “dn:String:String:String:String:dn|(1,2,3,4,5,6),(2,3,4,5,6,7),(3,4,5,6,7,8)"
3) Parity You could proceed very similar to the String operator, but you have to define a full string with the size of your system.
Best regards, Michele
-- ETH Zurich Michele Dolfi Institute for Theoretical Physics HIT G 32.4 Wolfgang-Pauli-Str. 27 8093 Zurich Switzerland
dolfim@phys.ethz.ch www.itp.phys.ethz.ch
+41 44 633 78 56 phone +41 44 633 11 15 fax
On Nov 8, 2015, at 4:16 PM, Henry Otobrise henryotobrise@gmail.com wrote:
Dear Michel, Thank you for your previous help on getting and using the Alps_mps_optim code. After waiting for the release of the Windows installer for the latest Alps version without success, I have eventually resolved to to build Alps from source on a Linux (Ubuntu 15.04) Os. However, I have some urgent question that I hope you can assit me with; 1.) I am installing the Alps 2.2.b4 version using cmake-gui. However, I kept getting the following error messages after what looked like a successful make process when I i) make test The following tests FAILED: 115 - expression (Failed) Errors while running CTest Makefile:137: recipe for target 'test' failed make: *** [test] Error 8
and when I disregard the error from the make test to
ii) make install
CMake Error at lib/pyalps/cmake_install.cmake:490 (file): file INSTALL cannot find "/opt/alps/lib/pyalps/pyalea_c.so". Call Stack (most recent call first): cmake_install.cmake:131 (include)
Makefile:66: recipe for target 'install' failed make: *** [install] Error 1
Kindly advise on how to resolve these problems. 2.) While building Alps (i.e. while running make), I kept getting the warning; using deprecated Numpy API, disable it by" "#defining NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION" [-wcpp]. Do I just ignore the warning or is there some thing I should do? 3.) How do I define, in the input parameter file for the Alps_mps_Optim code, the following correlation functions - Structure factor, S_k, the Parity Operator and the String Operator. Their definitions are given in the attached pdf file. Thank you, <HenrysDoc.pdf>