Installation on WIndows Cygwin

Question

Hi, I am trying to install itensor on my Windows laptop with Cygwin. While it is working well with Mac machine, Windows installation keep showing following error:

make[1]: Entering directory '/ITENSOR/itensor'
Compiling itensor/util/args.cc with optimizations
util/args.cc:8:31: fatal error: itensor/util/args.h: No such file or directory
compilation terminated.
Failure while executing command: g++ -m64 -std=c++11 -c -I/ITENSOR -I/openblas/include -fpermissive -DHAVELAPACKCONFIGH -DLAPACKCOMPLEXSTRUCTURE -O2 -DNDEBUG -Wall -DPLATFORMopenblas -DASSERTMACROSDEFINEVERSIONSWITHOUTUNDERSCORES=0 -DPLATFORMopenblas -DASSERTMACROSDEFINEVERSIONSWITHOUT_UNDERSCORES=0 -o util/args.o util/args.cc
make[1]: *** [Makefile:57: util/args.o] Error 1
make[1]: Leaving directory '/ITENSOR/itensor'
make: *** [Makefile:14: itensor] Error 2

It seems the directory is not properly included with -I flag, but I cannot find why. I would greatly appreciate it if anybody can advise this.

Thank you!

Comments

For information, it is WIndows 10 laptop and Cygwin is x86 64bit version, g++ installed(checked working with other codes).

---

Problem solved:
It was just the issue of Cygwin. Cygwin seems not recognizing -nix type paths. So I had to set paths explicitly, e.g. PREFIX=C:/cygwin64/ITENSOR, and similarly for -I and -L paths for lapack and blas. Hope it helps other Windows users that are not familiar with Cygwin as myself..  :)

Answer 1

Glad to hear you solved your problem! (And sorry about the slow reply.) Hope you are finding the library useful and great that it's working now.

Answer 2

Would you please upload or copy your mk file here? That will help me a lot. I have problem of mk file, too.

Comments

I did manually put commands instead of using mk file. However, it seems there were other problems after the installation.. I gave up using ITensor on Windows, and I am currently using ITensor in Linux virtual machine instead.

Answer 3

I was successfully able to get ITensor working using Cygwin on a laptop running Windows 10.

There are two steps, as follows:
1. Install Cygwin, making sure to put check marks for the options you want. Below I copied a write-up of the installation options I selected when I installed Cygwin:

---

First, download cygwin installation file, setup-x86_64.exe. It doesn't matter where it is saved.

Run the setup file. A large list of add-ons will be provided; you will need to check the following.

First click the box next to Debug, and click on the box under the column Bin? (but not Src?) for the following options:
->Debug
cygwindebuginfo
gccdebuginfo
lapackdebuginfo
Then click the box for the heading Devel, and select the following options:
-> Devel
binutils
cygwindevel
gcccore
gccg++
libargp
libcloogisl4
libltdl7
make
mingw64-i686-binutils
-gcc-core
-g++
-headers
-runtime
-windows-default-manifest
-winpthreads
mingw64-x8664-binutils
-gcc-ada
-gcc-g++
-headers
-runtime
-windwos default manifest
-winpthreads

->editors
nano (if you want the nano editor, otherwise vi is included with gcc-core)

Some of these might be added automatically when you select the main file. For instance, gcccore, gccg++ might automatically come with cygwin_devel but I forget which ones are automatic.

If these options are not sufficient simply re-install cygwin and add more options. I found some videos on youtube that were helpful.

Cygwin should be installed within the C: drive; it will then have its' own home file, within which you should create a user folder for yourself. In this user folder, install itensor.

In this way, cygwin creates a separate computer within your computer that acts like Linux. When you run the cygwin program, for instance by clicking on the cygwin icon on your desktop if you create a desktop icon, it will open up a unix-like shell that you can run itensor from. This cygwin shell then starts you at a "home" folder that is located within cygwin; from here you can use the shell just like you would in linux with the same navigation commands.

---

SECOND STEP. Add the following sections in your options.mk file (I only copied the relevant parts)

Section [1] ------------------------------

## GCC On Windows cygwin
## Extra flags are workaround for limitations
## of this compiler with Windows binary format
CCCOM=g++ -std=c++11 -Wa,-mbig-obj -O2

Section [2]------------------------------

##
## Example using a C interface to LAPACK on GNU/LINUX systems
## (Path to lib/ folder may differ on your system)
##

PLATFORM=lapack
##BLAS_LAPACK_LIBFLAGS=-lpthread -L/usr/lib -lblas -llapack
BLAS_LAPACK_LIBFLAGS=-L /usr/lib -lblas -llapack

Section [3]----------------------------------

## This step is optional, but if you wish to customize the flags
## used to compile optimized and debug code, you can do so here.

## Flags to give the compiler for "release mode"
OPTIMIZATIONS=-O2 -DNDEBUG -Wall

## Flags to give the compiler for "debug mode"
DEBUGFLAGS=-DDEBUG -g -Wall -pedantic -O2


###
### Other Makefile variables defined for convenience.
### Not necessary to modify these for most cases.
###

PREFIX=$(THIS_DIR)

ITENSOR_LIBDIR=$(PREFIX)/lib
ITENSOR_INCLUDEDIR=$(PREFIX)

OPTIMIZATIONS+= -DPLATFORM_$(PLATFORM) -
D__ASSERT_MACROS_DEFINE_VERSIONS_WITHOUT_UNDERSCORES=0
DEBUGFLAGS+= -DPLATFORM_$(PLATFORM) -
D__ASSERT_MACROS_DEFINE_VERSIONS_WITHOUT_UNDERSCORES=0

ITENSOR_LIBNAMES=itensor
ITENSOR_LIBFLAGS=$(patsubst %,-l%, $(ITENSOR_LIBNAMES))
ITENSOR_LIBFLAGS+= $(BLAS_LAPACK_LIBFLAGS)
ITENSOR_LIBGFLAGS=$(patsubst %,-l%-g, $(ITENSOR_LIBNAMES))
ITENSOR_LIBGFLAGS+= $(BLAS_LAPACK_LIBFLAGS)
ITENSOR_LIBS=$(patsubst %,$(ITENSOR_LIBDIR)/lib%.a, $(ITENSOR_LIBNAMES))
ITENSOR_GLIBS=$(patsubst %,$(ITENSOR_LIBDIR)/lib%-g.a, $(ITENSOR_LIBNAMES))

ITENSOR_INCLUDEFLAGS=-I$(ITENSOR_INCLUDEDIR) $(BLAS_LAPACK_INCLUDEFLAGS)

ifndef CCCOM
$(error Makefile variable CCCOM not defined in options.mk; please define it.)
endif

CCFLAGS=-I. $(ITENSOR_INCLUDEFLAGS) $(OPTIMIZATIONS) -Wno-unused-variable
CCGFLAGS=-I. $(ITENSOR_INCLUDEFLAGS) $(DEBUGFLAGS)
LIBFLAGS=-L$(ITENSOR_LIBDIR) $(ITENSOR_LIBFLAGS)
LIBGFLAGS=-L$(ITENSOR_LIBDIR) $(ITENSOR_LIBGFLAGS)

Note that it took Miles a long time to figure out the compiler workarounds in the above file. But since then I have been using it with no problems.