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Error installing mply library. Fatal error: gsl/gsl_sf.h: No such file or directory

I'm trying to install the latest version of mply (3.5.0) on xubuntu (ubuntu 17.10):
download the .tar.gz
Unzipped it
python setup.py build. Here I get the error displayed below.
also tried directly python setup.py install. same error.
tried installing gsl library by downloading the latest version, and following all the steps in https://coral.ise.lehigh.edu/jild13/2016/07/11/hello/. I have it installed in /home/gsl
still the same error
tried various other installations (sudo apt-get install libgsl0ldbl, sudo apt-get install libgs123, sudo apt-get install libgsl0-dev). Nothing works.
tried copying the folder /home/gsl/include/gsl inside the mply-3.5.0/mply/gsl folder . this slightly changes something, because now I get fatal error: gsl/gsl_sf_result.h: No such file or directory (So it finds gsl_sf.h, but not gsl_sf_result.h (both these files are present inside the /gsl/include/gsl folder).
tried with
python setup.py build_ext --include-dirs=/home/gls/include/gls
still nothing
tried to copy the /home/gsl/include/gsl folder inside my /usr/local/include:
cp -R /home/gsl/include/gsl /usr/local/include/gsl
still nothing.
Help!
Error message:
gcc -pthread -B /home/lorenzo/anaconda3/compiler_compat
-Wl,--sysroot=/ -Wsign-compare -DNDEBUG -g -fwrapv -O3 -Wall
-Wstrict-prototypes -fPIC -I/home/lorenzo/anaconda3/include/python3.6m
-I/home/lorenzo/anaconda3/lib/python3.6/site-packages/numpy/core/include
-I/home/lorenzo/anaconda3/include/python3.6m -c mlpy/gsl/gsl.c
-o build/temp.linux-x86_64-3.6/mlpy/gsl/gsl.o
mlpy/gsl/gsl.c:223:10: fatal error: gsl/gsl_sf.h: No such file or directory
#include "gsl/gsl_sf.h"

SOLVED by re-installing gsl library using conda:
conda install gsl

any way to set cython compiling with ucs2?

Hit problem when convert python code to shared object by Cython.
setup file here:
from distutils.core import setup
from Cython.Build import cythonize
setup(
ext_modules = cythonize("hello.py")
)
So everything works fine on my Ubuntu desktop util transferred to CentOS.
Got error:
undefined symbol: PyUnicodeUCS4_DecodeUTF8
I googled and find there are many questions on this, but, almost all of them say the root cause is python with UCS2 or UCS4, and I understand this, didn't find one show the way to solve this.
IMO, ways to solve:
rebuild python to get the right version by "--enable-unicode=ucs4/ucs2"
But I need to reinstall all packages
Compile the code from another desktop whose python with the right UCS
Now, I wanna if there is way to set Cython to compile with specified UCS mode.
Any suggestions is great appreciated.
Thanks.

First, to answer your actual question:
I wanna if there is way to set Cython to compile with specified UCS mode.
You can build a separate python installation from source and link Cython against its headers. To find the headers, you can use the python-config tool (or python3-config for Python 3). It is usually located in the bin directory where the python executable is:
$ # system python on my machine (macos):
$ which python-config
/usr/bin/python-config
$ # python 3 installation
$ which python3-config
/Library/Frameworks/Python.framework/Versions/3.6/bin/python3-config
$ python-config --cflags
-I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -fno-strict-aliasing -fno-common -dynamic -arch x86_64 -arch i386 -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE
$ python-config --ldflags
-L/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/config -lpython2.7 -ldl -framework CoreFoundation
Copy the output to the setup.py:
from setuptools import setup
from setuptools.extension import Extension
from Cython.Build import cythonize
cflags_ucs4 = [
'-I/Library/Frameworks/Python.framework/Versions/3.6/include/python3.6m',
'-I/Library/Frameworks/Python.framework/Versions/3.6/include/python3.6m',
...
]
ldflags_ucs4 = [
'-L/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/config-3.6m-darwin',
'-lpython3.6m',
...
]
cflags_ucs4 = [...]
ldflags_ucs2 = [...]
should_build_ucs2 = False # i.e. could be passed via sys.argv
if should_build_ucs2:
cflags = cflags_ucs2
ldflags = ldflags_ucs2
else:
cflags = cflags_ucs4
ldflags = ldflags_ucs4
extensions = [
Extension('hello.py', extra_compile_args=cflags, extra_link_args=ldflags),
]
setup(
ext_modules = cythonize(extensions)
)
However, I do not recommend doing that as you won't win anything by doing that - you will still need to build and distribute two separate packages (one for UCS2, another for UCS4) which is messy to maintain.
Instead, if you are building a wheel that should be installable on a wide range of Linux distros (what is most probably your actual goal), I would suggest to make your build compliable with PEP 513 (manylinux1 packages).I suggest you to read it through as it was very helpful for me when I faced the problem of distributing Linux-compliant wheels.
Now, one way to get a manylinux1-compliant wheel is to build the wheel on your machine, then running auditwheel to check for platform-specific issues and trying to resolve them:
$ pip install auditwheel
$ python setup.py bdist_wheel
$ # there should be now a mypkg-myver-cp36-cp36m-linux_x86_64.whl file in your dist directory
$ auditwheel show dist/mypkg-myver-cp36-cp36m-linux_x86_64.whl
$ # check what warnings auditwheel produced
$ # if there are warnings, try to repair them:
$ auditwheel repair dist/mypkg-myver-cp36-cp36m-linux_x86_64.whl
This should generate a wheel file named mypkg-myver-cp36-cp36m-manylinux1_x86_64.whl in a wheelhouse directory. Check again that everything is fine now by running auditwheel show wheelhouse/mypkg-myver-cp36-cp36m-manylinux1_x86_64.whl. If the wheel is now consistent with manylinux1, you can distribute it and it should work on most Linux distros (at least those with glibc; distros with musl like Alpine won't work, you will need to build a separate wheel if you want to support it).
What should you do if auditwheel can't repair your wheel? The best way is to pull a special docker container provided by PyPA for building manylinux1-compliant wheels (this is what I'm using myself):
$ docker pull https://quay.io/repository/pypa/manylinux1_x86_64
A wheel built inside this container will work on most of the Linux distros (excluding some exotic ones like Alpine).

Fatal error when trying to install PyCrypto on OS X El Capitan

I am trying to install PyCrypto on OS X 10.11.3 (El Capitan). I am using Python 3.5.1. I downloaded the gzip file from https://pypi.python.org/pypi/pycrypto and decompressed it. Then I ran python setup.py build like the instructions said and it appeared to do something, then it produced this output:
/usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -fwrapv -Wall -Wstrict-prototypes -std=c99 -O3 -fomit-frame-pointer -Isrc/ -I/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c src/MD2.c -o build/temp.macosx-10.6-intel-2.7/src/MD2.o
src/MD2.c:30:10: fatal error: 'string.h' file not found
#include <string.h>
^
1 error generated.
error: command '/usr/bin/clang' failed with exit status 1
I tried python3 setup.py build and got some very similar output:
/usr/bin/clang -fno-strict-aliasing -Wsign-compare -Wunreachable-code -fno-common -dynamic -fwrapv -Wall -Wstrict-prototypes -arch i386 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk -std=c99 -O3 -fomit-frame-pointer -Isrc/ -I/Library/Frameworks/Python.framework/Versions/3.5/include/python3.5m -c src/MD2.c -o build/temp.macosx-10.6-intel-3.5/src/MD2.o
src/MD2.c:30:10: fatal error: 'string.h' file not found
#include <string.h>
^
1 error generated.
error: command '/usr/bin/clang' failed with exit status 1
I tried Googling to figure out what to do, but I couldn't find anything useful. How can I install PyCrypto?
EDIT: I also tried several other things like pip install pycrypto and sudo pip3 install pycrypto and they didn't work. #l'L'l helped me get it to work by doing several strange, complex things that I never would have though have myself. They are summarized in the answer below.

Overview:
The manual build you're trying looks like it might be failing because it's referencing the OS X 10.6 SDK, which you likely don't have, and is outdated for the most part. Also, SDKs are now stored in a completely different location than when the 10.6 SDK was in it's prime.
New SDKs location:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/
Old SDKs location:
/Developer/SDKs/
Non-existent / outdated SDK:
Since it appears that when trying to build PyCrypto it's referencing the MacOSX10.6.sdk there are several things to consider:
Why does it reference an outdated SDK
Where is the SDK it's referencing set
What should be done to correct the issue
Unless we audit the source code carefully we might not know exactly where the incorrect flags are set, but we can do our best to work with the information we have. From the error we can see that there are several instances where the 10.6 SDK's name pops up:
/usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -isysroot /Developer/SDKs/MacOSX10.6.sdk -arch i386 -arch x86_64 -fwrapv -Wall -Wstrict-prototypes -std=c99 -O3 -fomit-frame-pointer -Isrc/ -I/Library
Building from source:
/Frameworks/Python.framework/Versions/2.7/include/python2.7 -c src/MD2.c -o build/temp.macosx-10.6-intel-2.7/src/MD2.o
src/MD2.c:30:10: fatal error: 'string.h' file not found
#include <string.h>
^
1 error generated.
error: command '/usr/bin/clang' failed with exit status 1
Analyzing this we can see that the PyCrypto's MD2.c file is trying to be built using the flag -isysroot /Developer/SDKs/MacOSX10.6.sdk. It might be worth trying pip instead:
Installing with pip:
...
fatal error: 'string.h' file not found #include <string.h>
...
Same error; we should probably find out if the <string.h> header even exists on the system — Let's make a quick test C application to find out:
Testing the C headers:
$ echo "#include <string.h>
#include <stdio.h>
int main() { printf(\"TEST\n\"); return 0; }" > t.c
$ clang t.c -o t
$ ./t
TEST
It's apparent the header does exist because the test worked fine. This tells us that the problem is more likely related directly to the 10.6 SDK (which doesn't seem to exist on the system).
Symlinking (non-existing) 10.6 SDK to 10.11 SDK:
Since we haven't determined where the SDK is actually getting set we'll go ahead and try to create symlinks so that any reference of the old 10.6 SDK links to the latest SDK (10.11 at this time):
$ cd /Developer/SDKs
$ sudo ln -s /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk MacOSX10.6.sdk
We can verify the symlink by issuing the following command:
$ ls -lat
total 8
drwxr-xr-x 3 root wheel 102 Feb 21 15:54 .
lrwxr-xr-x 1 root wheel 99 Feb 21 15:54 MacOSX10.6.sdk -> /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk
drwxr-xr-x 3 root wheel 102 Feb 21 15:52 ..
Now that we've successfully created the symlink let's try installing PyCrypto with pip once more:
$ sudo pip install pycrypto
Collecting pycrypto
Downloading pycrypto-2.6.1.tar.gz (446kB)
100% |████████████████████████████████| 446kB 1.2GB/s
Installing collected packages: pycrypto
Running setup.py install for pycrypto ... done
Successfully installed pycrypto-2.6.1
No errors! It looks like our problem is solved! Well, almost...
We still need to figure out what is responsible for setting the wrong (10.6) SDK during builds. Let's use the xcrun tool to see what the defaults are set at:
$ xcrun --show-sdk-version
10.11
The system default SDK is set to 10.11, so it must be get set incorrectly to 10.6 by Python, PyCrypto, or some other anomaly we might not have considered.
UPDATE:
After doing some recon it was discovered that Python 3 appears to be built with the OS X 10.6 SDK. In addition it's also setting the SDK to 10.6 and setting the (outdated) path in numerous places throughout the Python_Framework. There are so many references I won't bother listing them all, although here's an example:
Python_Framework Folder/Versions/3.5/lib/python3.5/config-3.5m/Makefile:79:CONFIGURE_CFLAGS= -arch i386 -arch x86_64 -isysroot /Developer/SDKs/MacOSX10.6.sdk
I can only assume the developers were trying to be as backward compatible as possible, however, it's unfortunately breaking forward compatibility in the process.
Notes:
Installing Python packages with pip can make life much easier in a lot of ways (package management, updating, uninstalling, etc.). For example installing PyCrypto should just be a matter of issuing the command:
$ sudo pip install pycrypto
If you have multiple Python's you can use the version number to install for that Python accordingly:
$ sudo pip3.5 install pycrypto
↳ https://pip.pypa.io/en/stable/installing/

I had what might be a related issue on OSX El Capitan when I would run pip install pycrypto. I was seeing RuntimeError: autoconf error. All I had to do was run sudo xcodebuild -license and type agree after reviewing the licence agreement. Afterward I was able to use pip to install pycrypto.

gcc error on install of tesseract-ocr

I am trying to run the following code on my mac.
import Image
enter code here`import pytesseract
im = Image.open('test.png')
print pytesseract.image_to_string(im)
Following the question from here: pytesseract-no such file or directory error
I need to install tesseract-ocr
but when I try to pip install tesseract-ocr I get the following errors:
creating build/temp.macosx-10.5-x86_64-2.7
gcc -fno-strict-aliasing -I//anaconda/include -arch x86_64 -DNDEBUG -g
-fwrapv -O3 -Wall -Wstrict-prototypes -I//anaconda/include/python2.7 -c
tesseract_ocr.cpp -o build/temp.macosx-10.5-x86_64-2.7/tesseract_ocr.o
tesseract_ocr.cpp:264:10:
fatal error: 'leptonica/allheaders.h' file not found #include "leptonica/allheaders.h"
^
1 error generated.
error: command 'gcc' failed with exit status 1
I don't know what to do.

You need install libtesseract-dev in your system;
sudo apt install libtesseract-dev

Use this with yum:
yum install leptonica-devel tesseract-devel

In Linux Use the Following Command
sudo apt-get install tesseract-ocr

refer another post, final solution on my Mac:
brew install tesseract
explanation:
it will install backend tesseract and dependent lib leptonica (and others libs: giflib, jpeg, libpng, libtiff, little-cms2, openjpeg, webp), so can fix this error.

try it like this without using space in between
"pip install easyocr"

Installing psycopg2 in virtualenv (Ubuntu 10.04, Python 2.5)

I had problems installing psycopg2 in a virtualenv.
I tried different things explained there: http://www.saltycrane.com/blog/2009/07/using-psycopg2-virtualenv-ubuntu-jaunty/
The last thing I tried is this...
I created a virtualenv with -p python2.5 --no-site-packages
I installed libpq-dev: apt-get install libpq-dev
In the virtualenv, I did this: easy_install -i http://downloads.egenix.com/python/index/ucs4/ egenix-mx-base
Then when I tried pip install psycopg2==2.0.7, I got this error:
Installing collected packages: psycopg2
Running setup.py install for psycopg2
building 'psycopg2._psycopg' extension
gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -DPSYCOPG_DEFAULT_PYDATETIME=1 -DPSYCOPG_VERSION="2.2.2 (dt dec ext pq3)" -DPG_VERSION_HEX=0x080404 -DPSYCOPG_EXTENSIONS=1 -DPSYCOPG_NEW_BOOLEAN=1 -DHAVE_PQFREEMEM=1 -DHAVE_PQPROTOCOL3=1 -I/usr/include/python2.5 -I. -I/usr/include/postgresql -I/usr/include/postgresql/8.4/server -c psycopg/psycopgmodule.c -o build/temp.linux-i686-2.5/psycopg/psycopgmodule.o -Wdeclaration-after-statement
psycopg/psycopgmodule.c:27:20: error: Python.h: No such file or directory
In file included from psycopg/psycopgmodule.c:31:
./psycopg/python.h:31:26: error: structmember.h: No such file or directory
./psycopg/python.h:34:4: error: #error "psycopg requires Python >= 2.4"
In file included from psycopg/psycopgmodule.c:32:
Does anyone have any idea how to solve that?
Thanks.

From python-list:
Diez:
Install the python-dev-package. It
contains the Python.h file, which the
above error message pretty clearly
says. Usually, it's a good idea to
search package descriptions of
debian/ubuntu packages for missing
header files to know what to install.
Pascal:
It's already installed; at least for
Python 2.6, nor sure it's correct for
Python 2.5. python2.5-dev is not available but
python-old-doctools seems to replace it.
Diez:
It is 100% not correct for
python2.5. As the error message shows
- it's missing.
If it's not available somewhere, you
should consider building python
yourself, if you have to use 2.5.
Alex:
Ubuntu 10.04 doesn't have a full
Python 2.5 packaged, as evidenced by
the lack of python2.5-dev. You need to
use Python 2.6 or if you absolutely
must use Python 2.5 build it from
source, try a Debian package or switch
distro. python-old-doctools does not
replace python- dev, it looks like it
was bodged to keep some latex tools
working.
Pascal: I finally created a virtualenv
with Python 2.6 and everything went fine
(with the latest version of psycopg2).