Error in installing face_recognition library - python-3.x

Question

How to solve the below mentioned cmake error while installing the face_recognition library?
Collecting face_recognition
Using cached face_recognition-1.2.1-py2.py3-none-any.whl
Requirement already satisfied: face-recognition-models>=0.3.0 in ./anaconda/lib/python3.6/site-packages (from face_recognition)
Requirement already satisfied: Pillow in ./anaconda/lib/python3.6/site-packages (from face_recognition)
Requirement already satisfied: Click>=6.0 in ./anaconda/lib/python3.6/site-packages (from face_recognition)
Requirement already satisfied: scipy>=0.17.0 in ./anaconda/lib/python3.6/site-packages (from face_recognition)
Collecting dlib>=19.7 (from face_recognition)
Using cached dlib-19.10.0.tar.gz
Requirement already satisfied: numpy in ./anaconda/lib/python3.6/site-packages (from face_recognition)
Requirement already satisfied: olefile in ./anaconda/lib/python3.6/site-packages (from Pillow->face_recognition)
Building wheels for collected packages: dlib
Running setup.py bdist_wheel for dlib ... error
Complete output from command /Users/muralidharan/anaconda/bin/python -u -c "import setuptools, tokenize;__file__='/private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" bdist_wheel -d /var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/tmpw6lzrrukpip-wheel- --python-tag cp36:
running bdist_wheel
running build
running build_py
package init file 'dlib/__init__.py' not found (or not a regular file)
running build_ext
Invoking CMake setup: 'cmake /private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/tools/python -DCMAKE_LIBRARY_OUTPUT_DIRECTORY=/private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/build/lib.macosx-10.7-x86_64-3.6 -DPYTHON_EXECUTABLE=/Users/muralidharan/anaconda/bin/python -DCMAKE_BUILD_TYPE=Release'
error: [Errno 2] No such file or directory: 'cmake'
----------------------------------------
Failed building wheel for dlib
Running setup.py clean for dlib
Failed to build dlib
Installing collected packages: dlib, face-recognition
Running setup.py install for dlib ... error
Complete output from command /Users/muralidharan/anaconda/bin/python -u -c "import setuptools, tokenize;__file__='/private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-qhc3clwr-record/install-record.txt --single-version-externally-managed --compile:
running install
running build
running build_py
package init file 'dlib/__init__.py' not found (or not a regular file)
running build_ext
Invoking CMake setup: 'cmake /private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/tools/python -DCMAKE_LIBRARY_OUTPUT_DIRECTORY=/private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/build/lib.macosx-10.7-x86_64-3.6 -DPYTHON_EXECUTABLE=/Users/muralidharan/anaconda/bin/python -DCMAKE_BUILD_TYPE=Release'
error: [Errno 2] No such file or directory: 'cmake'
----------------------------------------
Command "/Users/muralidharan/anaconda/bin/python -u -c "import setuptools, tokenize;__file__='/private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-qhc3clwr-record/install-record.txt --single-version-externally-managed --compile" failed with error code 1 in /private/var/folders/xz/rcv9f_6x41gcvhrqzsd6mrxw0000gn/T/pip-build-5zqyoigf/dlib/

Answer 1

As to me, I install face_recognition in ubuntu16 python2.7, I write a shell to install it.
#!/bin/bash
# This shell script install face_recognition in ubuntu16 python2.7
apt-get -y install git
apt-get -y install cmake
# install dlib without cuda
git clone https://github.com/davisking/dlib.git
cd dlib
mkdir build; cd build; cmake .. ; cmake --build .
# install dlib python interface
cd -
apt-get -y install python-setuptools
apt-get -y install python-dev
python setup.py install
# install face_recognition
apt-get -y install python-pip
pip install face_recognition

Answer 2

error: [Errno 2] No such file or directory: 'cmake'
I ran into the same problem recently, I resolved it downloading CMAKE.
Here is the link to download it for each OS