diff --git a/.travis.yml b/.travis.yml
index c73dec6..bff0eb1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,35 +1,54 @@
 language: python
 
 python:
-  - "2.7"
-  - "3.4"
-  - "3.5"
-  - "3.6"
+  - 2.7
+  - 3.5
+  - 3.6
+
+env:
+  - NCO_VERSION=4.5.5
+  - NCO_VERSION=4.6.1
+  - NCO_VERSION=latest
 
 before_install:
-  - sudo apt-get update
-  - sudo apt-get install libnetcdf-dev nco
-  # We do this conditionally because it saves us some downloading if the
-  # version is the same.
-  - if [[ "$TRAVIS_PYTHON_VERSION" == "2.7" ]]; then
-      wget https://repo.continuum.io/miniconda/Miniconda2-latest-Linux-x86_64.sh -O miniconda.sh;
-    else
-      wget https://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh -O miniconda.sh;
-    fi
+  # Install miniconda
+  # -----------------
+  - export CONDA_BASE=http://repo.continuum.io/miniconda/Miniconda
+  - wget ${CONDA_BASE}3-latest-Linux-x86_64.sh -O miniconda.sh;
   - bash miniconda.sh -b -p $HOME/miniconda
   - export PATH="$HOME/miniconda/bin:$PATH"
-  - hash -r
+
+  # Create the basic testing environment
+  # ------------------------------------
   - conda config --set always_yes yes --set changeps1 no
-  - conda update -q conda
-  # Useful for debugging any issues with conda
-  - conda info -a
+  - conda config --set show_channel_urls True
+  - conda config --add create_default_packages pip
+  - conda update --quiet conda
+
+  # Add 3rd party channels
+  # ------------------------------------
+  - conda config --add channels conda-forge
 
-  # Make Conda test environment
-  - conda env create --file ci/requirements-$TRAVIS_PYTHON_VERSION.yml
+  # Create our environment
+  # ------------------------------------
+  - conda env create --name test_env --quiet --file ci/requirements-$TRAVIS_PYTHON_VERSION.yml
   - source activate test_env
+  - if [ "${NCO_VERSION}" == "latest" ];
+    then conda install nco;
+    else conda install nco==${NCO_VERSION};
+    fi
+
+  # Debugging information
+  # ------------------------------------
+  - conda info -a
+  - conda list --export
+  - which ncks ncdump
+
+  # Install pynco
+  # ------------------------------------
   - python setup.py install
 
 # command to run tests
 script:
   - python -c "from nco import Nco"
-  - py.test
+  - py.test -rxs -s -v
diff --git a/README.md b/README.md
index 3309da1..819ee74 100644
--- a/README.md
+++ b/README.md
@@ -1,192 +1,262 @@
-pynco
-============
+# pynco
 
 Python bindings for [NCO](http://nco.sourceforge.net/).  A fork from Ralf Mueller's [cdo-bindings](https://github.com/Try2Code/cdo-bindings).
 
 ## `pynco` - Use Python to access the power of [NCO](http://nco.sourceforge.net/)
 
-This package contains the module python `nco`, which implements a python style access to
-the [NetCDF Operators (NCO)](http://nco.sourceforge.net/). NCO is a command line tool for processing
-netCDF data. Its main focus is climate data, but it can by used for other
-purposes too.
+This package contains the module python `nco`, which implements a python style access to the [NetCDF Operators (NCO)](http://nco.sourceforge.net/). NCO is a command line tool for processing netCDF data. Its main focus is climate data, but it can by used for other purposes too.
+
 
 ## Installation
 
-### Python Installation:
+### Conda Installation (recommended)
+
+This will install all required and optional dependencies and is the quickest and easiest way to a working `pynco` installation.
+
+```bash
+conda install -c conda-forge pynco
+```
+
+### Pypi Installation
+
+Please see [the requirements](#requirements) before installing
 
-    python setup.py install
+```bash
+pip install nco
+```
 
-### Pypi Installation:
+### Python Installation
 
-    pip install nco
+Please see [the requirements](#requirements) before installing
 
-### Conda Installation:
+```bash
+python setup.py install
+```
 
-     conda install -c conda-forge pynco
 
 ### Requirements
 
-- ***Platform***: Unix or Mac OS (Windows has not bee tested)
-- [NetCDF Operators (NCO)](http://nco.sourceforge.net/) - Version 4.2 or later
-- Python 2.7, 3.4, or later
+**Mandatory**
+
+-  ***Platform***: Unix or Mac OS (Windows has not bee tested)
+-  [NetCDF Operators (NCO)](http://nco.sourceforge.net/) - Version 4.2 or later. We don't test against every NCO version.
+-  Python 2.7, 3.4, 3.5, or 3.6
+
+**Recommended**
+
+These will allow `pynco` operations to return `numpy` arrays
+
+-  [scipy](http://docs.scipy.org/doc/scipy/reference/generated/scipy.io.netcdf.netcdf_file.html)
+-  [netCDF-4](https://code.google.com/p/netcdf4-python/)
+-  [numpy](http://www.numpy.org/)
 
-**Recommended dependencies for returning `numpy` arrays from `nco` operations**
-- [scipy](http://docs.scipy.org/doc/scipy/reference/generated/scipy.io.netcdf.netcdf_file.html)
-- [netCDF-4](https://code.google.com/p/netcdf4-python/)
-- [numpy](http://www.numpy.org/)
 
 ## Usage
 
 #### Importing the Nco class
 
-   `from nco import Nco`
+```python
+from nco import Nco
+```
 
 ### Run operators
 
 For python an instance has to be created first
 
-    from nco import Nco
-    nco = Nco()
+```python
+from nco import Nco
+nco = Nco()
+```
 
-Now any NCO command (i.e. ncks, ncra, ...) can be called as a method of `nco`.
+Now any NCO command (i.e. `ncks`, `ncra`, ...) can be called as a method of `nco`.
 
-* Required argument
-   - input - Input netcdf file name, str
+* Required arguments
+    -  `input` - Input netcdf file name, str
 
 * Optional arguments
-    - `output` - String or list of strings representing input netCDF filenames.  If not provided and operator returns a file (not an array or stdout text), the method will return a temporary file.
-    - `debug` - bool or int, if <0 or True, debug statements will be turned on for NCO and NCOpy (default=False)
-    - `returnCdf` - return a netCDF file handle, bool (default=False)
-    - `returnArray` - return a numpy array of variable name, str (default='')
-    - `returnMaArray` - return a numpy masked array of variable name, str (default='')
-    - `options` - a string of NCO input options, for example options='-7 -L 1' (default='')
-    - `Atted`   - a wrapper object to be used for ncatted. Atted objects can be included in the options list
-    -  `Limit`  - a wrapper object for the hyperslab ( -d ) command line option
-    -  `Rename` - a wrapper object for the -d, -a, -v, -g command line options in ncrename
-    - `**kwargs` - any kwarg will be passed as a key, value pair to the nco command `--{key}={value}`.  This allows the user to pass any number of long name commands list in the nco help pages.
+
+    -  `output` - `str` or `list` of strings representing input netCDF filenames.  If not provided and operator returns a file (not an array or stdout text), the method will return a temporary file.
+    - `debug` - `bool` or `int`, if less than 0 or True, debug statements will be turned on for NCO and NCOpy (default: `False`)
+    -  `returnCdf` - `bool`, return a netCDF file handle (default: `False`)
+    -  `returnArray` - `str`. return a numpy array of variable name (default: `''`)
+    -  `returnMaArray` - `str`. return a numpy masked array of variable name (default: `''`)
+    -  `options` - `list`, NCO input options, for example `options=['-7', '-L 1']` (default: `[]`)
+    -  `Atted` - a wrapper object to be used for ncatted. Atted objects can be included in the options list
+    -  `Limit` - a wrapper object for the hyperslab (`-d`) command line option
+    -  `Rename` - a wrapper object for the `-d`, `-a`, `-v`, and `-g` command line options in `ncrename`
+    -  `**kwargs` - any kwarg will be passed as a key, value pair to the nco command `--{key}={value}`.  This allows the user to pass any number of long name commands list in the nco help pages.
+
 
 ### Examples
 
-* File information:
+*  File information:
 
-        ncdump_string = nco.ncdump(input=ifile)
+    ```python
+    ncdump_string = nco.ncdump(input=ifile)
+    ```
 
-* Operators with user defined regular output files:
+*  Operators with user defined regular output files:
 
-        nco.ncra(input=ifile, output=ofile)
+    ```python
+    nco.ncra(input=ifile, output=ofile)
+    ```
 
-* Use temporary output files:
+*  Use temporary output files:
 
-        temp_ofile = nco.ncrcat(input=ifile)
+    ```python
+    temp_ofile = nco.ncrcat(input=ifile)
+    ```
 
-* Set global NCO options:
+*  Set global NCO options:
 
-		nco.ncks(input=ifile, output=ofile, options="--netcdf4")
+    ```python
+    nco.ncks(input=ifile, output=ofile, options="--netcdf4")
+    ```
 
-* Return multi-dimension arrays:
+*  Return multi-dimension arrays:
 
-		temperatures = nco.ncra(input=ifile, returnArray=True).variables['T'][:]
-		temperatures = nco.ncra(input=ifile, returnCdf=True).variables['T'][:]
-		temperatures = nco.ncra(input=ifile, returnArray='T')
+    ```python
+    temperatures = nco.ncra(input=ifile, returnArray=True).variables['T'][:]
+    temperatures = nco.ncra(input=ifile, returnCdf=True).variables['T'][:]
+    temperatures = nco.ncra(input=ifile, returnArray='T')
+    ```
 
 * Wrapper Objects
 
-		The Atted opject is a convienent wrapper object to the `-a` command-line switch in ncatted.
-		The Limit object is a wrapper to the `-d` command-line switch.
-		The Rename is a wrapper for the `-a,  -v, -d , -g ` switches in ncrename.
+    The Atted opject is a convienent wrapper object to the `-a` command-line switch in ncatted.
+    The Limit object is a wrapper to the `-d` command-line switch.
+    The Rename is a wrapper for the `-a,  -v, -d , -g ` switches in ncrename.
+
+    e.g  the following are equivalent:
 
-  	e.g  the following are equivalent:
-	```
-        ncatted -a _FillValue,three_dmn,o,d,-9.91e+33 in.nc
-        nco.ncatted(input="in.nc",options=[c.atted("overwrite","_FillValue","three_dmn",-9.91e+33,'d')])     
-	```
-     	see more examples below
+    ```
+    ncatted -a _FillValue,three_dmn,o,d,-9.91e+33 in.nc
+    nco.ncatted(input="in.nc",options=[c.atted("overwrite","_FillValue","three_dmn",-9.91e+33,'d')])
+    ```
 
 ## Tempfile helpers
 
 `pynco` includes a simple tempfile wrapper, which makes life easier.  In the
-absence of a specified output file, `Nco()` will create a temporary file to allow the results of the task to be returned to the user.  For example:
+absence of a specified output file, `pynco` will create a temporary file to allow the results of the task to be returned to the user.  For example:
+
+```python
+temperatures = nco.ncra(input=ifile, returnArray='T')
+```
 
-    temperatures = nco.ncra(input=ifile, returnArray='T')
 is equivalent to:
 
-    temperatures = nco.ncra(input=ifile, output=tempfile.mktemp(), returnArray='T')
+```
+temperatures = nco.ncra(input=ifile, output=tempfile.mktemp(), returnArray='T')
+```
 
-* Atted wrapper
 
+##  Atted wrapper
 
-	It is sometimes more tidy to define the atted objects in a separate list then add that list the options in the nco call
+It is sometimes more tidy to define the atted objects in a separate list then add that list the options in the nco call
 
-    ```
-    opt=[   
-         c.Atted("o", "units", "temperature", "Kelvin"),
-         c.Atted("c", "min", "temperature", 0.16,'d' ),
-         c.Atted("m", "max", "temperature", 283.01,'float64'),
-         c.Atted("c", "bnds","time",[0.5,1.5],'f')
-        ]  
-    nco.ncatted(input="in.nc",options=opt)     
-    ```
+```python
+opt = [
+    c.Atted("o", "units", "temperature", "Kelvin"),
+    c.Atted("c", "min", "temperature", 0.16, 'd'),
+    c.Atted("m", "max", "temperature", 283.01, 'float64'),
+    c.Atted("c", "bnds", "time", [0.5, 1.5], 'f')
+]
+nco.ncatted(input="in.nc", options=opt)
+```
 
-   You can also use keyword arguments in the call so the above options become
+You can also use keyword arguments in the call so the above options become
 
-    ```
-    opt=[c.Atted(mode="o", attName="units", varName="temperature", Value="Kelvin",sType="c"),
-         c.Atted(mode="create", attName="min", varName="temperature", Value=0.16,sType='d' ),
-         c.Atted(mode="modify", attName="max", varName="temperature", Value=283.01,sType='float64'),
-         c.Atted(mode="create", attName="bnds", varName="time", Value=[0.5,1.5],sType='float32')
-        ]  
-    ```  
+```python
+opt = [
+    c.Atted(mode="o", attName="units", varName="temperature", Value="Kelvin", sType="c"),
+    c.Atted(mode="create", attName="min", varName="temperature", Value=0.16, sType='d' ),
+    c.Atted(mode="modify", attName="max", varName="temperature", Value=283.01, sType='float64'),
+    c.Atted(mode="create", attName="bnds", varName="time", Value=[0.5, 1.5], sType='float32')
+]
+nco.ncatted(input="in.nc", options=opt)
+```
 
-    Value can be a single value  or a list ( or any python iterable type or a numpy array).
+#### `Value`
 
-    If sType is NOT included then the type is inferred from the first value in the list<br/>
-    if sType is included then any values in the list are NOT of sType are converted to sType<br/><br/>
+Can be a single value or a list (or any python iterable type or a numpy array).
 
-    For sType you can use the following:
-    f, d, l/i, s, b, ub, us, u, ll, ull         
-    Or their numpy equivalents
-    float32, float64, int32, int16, byte, ubyte, uint16, uint32, int64, uint64    
+*  If sType **is not** included then the type is inferred from the first value in the list
+*  If sType **is** included then any values in the list are **not** of sType are converted to the sType
 
-    For a netCDF3 character string use "c"or "char"<br/>
-    For netCDF4 string(s) use "sng" or "string"<br/>
+#### `sType`
 
-    For mode you can use the single character abbreviations as per ncatted or the following words:<br/>
-    (a)ppend, (c)reate, (d)elete, (m)odify, (n)append, (o)verwrite<br/>
+You can use the following: `f, d, l/i, s, b, ub, us, u, ll, ull`
+Or their numpy equivalents: `float32, float64, int32, int16, byte, ubyte, uint16, uint32, int64, uint64`
 
-* Limit and LimitSingle wrapper
+For a netCDF3 character string use `c` or `char`
+For netCDF4 string(s) use `sng` or `string`
 
-	the following are equivalent
-    ```
-   ncks -d time,0,8,2 -d time,10 -d lat,-20.0,20.0 -d lon,50.0,350.0  -d lev,,,4
-   and
-   opt=[
-  		c.Limit("time",0,8,2),
-		c.LimitSingle("time",10),
-		c.Limit("lat",-20.0,20.0),
-		c.Limit(dmn_name="lon",srt=50.0,end=350.0), 	
-		c.Limit(dmn_name="lev",srd=4)
-       ]
+#### `mode`
+
+For mode you can use the single character abbreviations as per `ncatted`: `a, c, d, m, n, o` or the following words: `a)ppend, create, delete, modify, overwrite`
+
+
+##  Limit and LimitSingle wrapper
+
+The following are equivalent:
+
+**nco**
+
+```bash
+ncks -d time,0,8,2 -d time,10 -d lat,-20.0,20.0 -d lon,50.0,350.0  -d lev,,,4
+```
+
+**pynco**
+
+```python
+opt = [
+    c.Limit("time", 0, 8, 2),
+    c.LimitSingle("time", 10),
+    c.Limit("lat", -20.0, 20.0),
+    c.Limit(dmn_name="lon", srt=50.0, end=350.0),
+    c.Limit(dmn_name="lev", srd=4)
+]
+
+nco.ncks(input="in.nc", output="out.nc", options=opt)
+```
+
+##  Rename wrapper
+
+The following are equivalent:
+
+**`nco`**
+
+```bash
+ncrename -v p,pressure -v t,temperature in.nc
+```
+
+**`pynco`**
 
-   nco.ncks(input="in.nc", output="out.nc", options=opt)
-   ```
+```python
+rDict = {
+    'p': 'pressure',
+    't': 'temperature'
+}
+nco.ncrename(input="in.nc", options=[ c.Rename("variable", rDict) ])
+```
 
-* Rename wrapper
+Also equivalent:
 
-  the  following are equivalent:
-  ```
-  ncrename -v p,pressure -v t,temperature in.nc
+**`nco`**
 
-  rDict={'p':'pressure', 't':'temperature'}   
-  nco.ncrename(input="in.nc", options=[ c.Rename("variable",rDict)])
-  ```
+```bash
+ncrename -d lon,longitude -d lat,latitude -v lon,longitude -v lat,latitude in.nc
+```
 
-  rename coordinate variables (dim & var)
-  ```
-  ncrename -d lon,longitude -d lat,latitude -v lon,longitude -v lat,latitude in.nc
+**`pynco`**
 
-  rDict={'lon':'longitude', 'lat':'latitude'}   
-  nco.ncrename(input="in.nc", options=[c.Rename("d",rDict),  c.Rename("v",rDict)])
-  ```
+```python
+rDict = {
+    'lon': 'longitude',
+    'lat': 'latitude'
+}
+nco.ncrename(input="in.nc", options=[ c.Rename("d", rDict), c.Rename("v", rDict) ])
+```
 
 ## Support, Issues, Bugs, ...
 
@@ -199,7 +269,6 @@ For usage questions, please use [Stack Overflow](https://stackoverflow.com/quest
 
 `pynco` makes use of the GPLv2 License, see LICENSE.txt.
 
----
 
 ## Other stuff
 
diff --git a/ci/requirements-2.7.yml b/ci/requirements-2.7.yml
index c173559..c1bb473 100644
--- a/ci/requirements-2.7.yml
+++ b/ci/requirements-2.7.yml
@@ -1,9 +1,8 @@
-name: test_env
 channels:
   - conda-forge
 dependencies:
   - python=2.7
-  - dateutil
+  - python-dateutil
   - h5py
   - netCDF4
   - numpy
diff --git a/ci/requirements-3.4.yml b/ci/requirements-3.4.yml
index e1f4828..6fd71ff 100644
--- a/ci/requirements-3.4.yml
+++ b/ci/requirements-3.4.yml
@@ -1,9 +1,8 @@
-name: test_env
 channels:
   - conda-forge
 dependencies:
   - python=3.4
-  - dateutil
+  - python-dateutil
   - h5py
   - netCDF4
   - numpy
diff --git a/ci/requirements-3.5.yml b/ci/requirements-3.5.yml
index e96e5af..184febe 100644
--- a/ci/requirements-3.5.yml
+++ b/ci/requirements-3.5.yml
@@ -1,9 +1,8 @@
-name: test_env
 channels:
   - conda-forge
 dependencies:
   - python=3.5
-  - dateutil
+  - python-dateutil
   - h5py
   - netCDF4
   - numpy
diff --git a/ci/requirements-3.6.yml b/ci/requirements-3.6.yml
index 879e472..a93960b 100644
--- a/ci/requirements-3.6.yml
+++ b/ci/requirements-3.6.yml
@@ -1,9 +1,8 @@
-name: test_env
 channels:
   - conda-forge
 dependencies:
   - python=3.6
-  - dateutil
+  - python-dateutil
   - h5py
   - netCDF4
   - numpy
diff --git a/docs/index.md b/docs/index.md
index 0b8a0ed..0ca1ce1 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -1,111 +1,263 @@
-pynco
-============
-Use Python to access the power of [NCO](http://nco.sourceforge.net/)
+# pynco
 
 Python bindings for [NCO](http://nco.sourceforge.net/).  A fork from Ralf Mueller's [cdo-bindings](https://github.com/Try2Code/cdo-bindings).
 
-This package contains the module python `nco`, which implements a python style access to
-the [NetCDF Operators (NCO)](http://nco.sourceforge.net/). NCO is a command line tool for processing
-netCDF data. Its main focus is climate data, but it can by used for other
-purposes too.
+## `pynco` - Use Python to access the power of [NCO](http://nco.sourceforge.net/)
+
+This package contains the module python `nco`, which implements a python style access to the [NetCDF Operators (NCO)](http://nco.sourceforge.net/). NCO is a command line tool for processing netCDF data. Its main focus is climate data, but it can by used for other purposes too.
+
 
 ## Installation
 
-### Python Installation:
+### Conda Installation (recommended)
 
-    python setup.py install
+This will install all required and optional dependencies and is the quickest and easiest way to a working `pynco` installation.
 
-### PyPI Installation:
+```bash
+conda install -c conda-forge pynco
+```
 
-    pip install nco
+### Pypi Installation
 
-    ### Conda Installation:
+Please see [the requirements](#requirements) before installing
+
+```bash
+pip install nco
+```
+
+### Python Installation
+
+Please see [the requirements](#requirements) before installing
+
+```bash
+python setup.py install
+```
 
-         conda install -c conda-forge pynco
 
 ### Requirements
 
-- ***Platform***: Unix or Mac OS (Windows has not bee tested)
-- [NetCDF Operators (NCO)](http://nco.sourceforge.net/) - Version 4.2 or later
-- Python 2.7, 3.4, or later
+**Mandatory**
+
+-  ***Platform***: Unix or Mac OS (Windows has not bee tested)
+-  [NetCDF Operators (NCO)](http://nco.sourceforge.net/) - Version 4.2 or later. We don't test against every NCO version.
+-  Python 2.7, 3.4, 3.5, or 3.6
+
+**Recommended**
+
+These will allow `pynco` operations to return `numpy` arrays
+
+-  [scipy](http://docs.scipy.org/doc/scipy/reference/generated/scipy.io.netcdf.netcdf_file.html)
+-  [netCDF-4](https://code.google.com/p/netcdf4-python/)
+-  [numpy](http://www.numpy.org/)
 
-**Recommended dependencies for returning `numpy` arrays from `nco` operations**
-- [scipy](http://docs.scipy.org/doc/scipy/reference/generated/scipy.io.netcdf.netcdf_file.html)
-- [netCDF-4](https://code.google.com/p/netcdf4-python/)
-- [numpy](http://www.numpy.org/)
 
 ## Usage
 
 #### Importing the Nco class
 
-   `from nco import Nco`
+```python
+from nco import Nco
+```
 
 ### Run operators
 
 For python an instance has to be created first
 
-```Python
+```python
 from nco import Nco
 nco = Nco()
 ```
 
 Now any NCO command (i.e. `ncks`, `ncra`, ...) can be called as a method of `nco`.
 
-* Required argument
-   - input - Input netCDF file name, str
+* Required arguments
+    -  `input` - Input netcdf file name, str
 
 * Optional arguments
-    - `output` - String or list of strings representing input netCDF filenames.  If not provided and operator returns a file (not an array or stdout text), the method will return a temporary file.
-    - `debug` - bool or int, if <0 or True, debug statements will be turned on for NCO and NCOpy (default=False)
-    - `returnCdf` - return a netCDF file handle, bool (default=False)
-    - `returnArray` - return a numpy array of variable name, str (default='')
-    - `returnMaArray` - return a numpy masked array of variable name, str (default='')
-    - `options` - a string of NCO input options, for example options='-7 -L 1' (default='')
-    - `**kwargs` - any kwarg will be passed as a key, value pair to the nco command `--{key}={value}`.  This allows the user to pass any number of long name commands list in the nco help pages.
+
+    -  `output` - `str` or `list` of strings representing input netCDF filenames.  If not provided and operator returns a file (not an array or stdout text), the method will return a temporary file.
+    - `debug` - `bool` or `int`, if less than 0 or True, debug statements will be turned on for NCO and NCOpy (default: `False`)
+    -  `returnCdf` - `bool`, return a netCDF file handle (default: `False`)
+    -  `returnArray` - `str`. return a numpy array of variable name (default: `''`)
+    -  `returnMaArray` - `str`. return a numpy masked array of variable name (default: `''`)
+    -  `options` - `list`, NCO input options, for example `options=['-7', '-L 1']` (default: `[]`)
+    -  `Atted` - a wrapper object to be used for ncatted. Atted objects can be included in the options list
+    -  `Limit` - a wrapper object for the hyperslab (`-d`) command line option
+    -  `Rename` - a wrapper object for the `-d`, `-a`, `-v`, and `-g` command line options in `ncrename`
+    -  `**kwargs` - any kwarg will be passed as a key, value pair to the nco command `--{key}={value}`.  This allows the user to pass any number of long name commands list in the nco help pages.
+
 
 ### Examples
 
-* Operators with user defined regular output files:
+*  File information:
 
-```Python
-nco.ncra(input=ifile, output=ofile)
-```
+    ```python
+    ncdump_string = nco.ncdump(input=ifile)
+    ```
 
-* Use temporary output files:
+*  Operators with user defined regular output files:
 
-```Python
-temp_ofile = nco.ncrcat(input=ifile)
-```
+    ```python
+    nco.ncra(input=ifile, output=ofile)
+    ```
 
-* Set global NCO options:
+*  Use temporary output files:
 
-```Python
-nco.ncks(input=ifile, output=ofile, options="--netcdf4")
-```
+    ```python
+    temp_ofile = nco.ncrcat(input=ifile)
+    ```
 
-* Return multi-dimension arrays:
+*  Set global NCO options:
 
-```Python
-temperatures = nco.ncra(input=ifile, returnArray=True).variables['T'][:]
-temperatures = nco.ncra(input=ifile, returnCdf=True).variables['T'][:]
-temperatures = nco.ncra(input=ifile, returnArray='T')
-```
+    ```python
+    nco.ncks(input=ifile, output=ofile, options="--netcdf4")
+    ```
+
+*  Return multi-dimension arrays:
+
+    ```python
+    temperatures = nco.ncra(input=ifile, returnArray=True).variables['T'][:]
+    temperatures = nco.ncra(input=ifile, returnCdf=True).variables['T'][:]
+    temperatures = nco.ncra(input=ifile, returnArray='T')
+    ```
+
+* Wrapper Objects
+
+    The Atted opject is a convienent wrapper object to the `-a` command-line switch in ncatted.
+    The Limit object is a wrapper to the `-d` command-line switch.
+    The Rename is a wrapper for the `-a,  -v, -d , -g ` switches in ncrename.
+
+    e.g  the following are equivalent:
+
+    ```
+    ncatted -a _FillValue,three_dmn,o,d,-9.91e+33 in.nc
+    nco.ncatted(input="in.nc",options=[c.atted("overwrite","_FillValue","three_dmn",-9.91e+33,'d')])
+    ```
 
 ## Tempfile helpers
 
 `pynco` includes a simple tempfile wrapper, which makes life easier.  In the
-absence of a specified output file, `Nco()` will create a temporary file to allow the results of the task to be returned to the user.  For example:
+absence of a specified output file, `pynco` will create a temporary file to allow the results of the task to be returned to the user.  For example:
 
-```Python
+```python
 temperatures = nco.ncra(input=ifile, returnArray='T')
 ```
 
 is equivalent to:
 
-```Python
+```
 temperatures = nco.ncra(input=ifile, output=tempfile.mktemp(), returnArray='T')
 ```
 
+
+##  Atted wrapper
+
+It is sometimes more tidy to define the atted objects in a separate list then add that list the options in the nco call
+
+```python
+opt = [
+    c.Atted("o", "units", "temperature", "Kelvin"),
+    c.Atted("c", "min", "temperature", 0.16, 'd'),
+    c.Atted("m", "max", "temperature", 283.01, 'float64'),
+    c.Atted("c", "bnds", "time", [0.5, 1.5], 'f')
+]
+nco.ncatted(input="in.nc", options=opt)
+```
+
+You can also use keyword arguments in the call so the above options become
+
+```python
+opt = [
+    c.Atted(mode="o", attName="units", varName="temperature", Value="Kelvin", sType="c"),
+    c.Atted(mode="create", attName="min", varName="temperature", Value=0.16, sType='d' ),
+    c.Atted(mode="modify", attName="max", varName="temperature", Value=283.01, sType='float64'),
+    c.Atted(mode="create", attName="bnds", varName="time", Value=[0.5, 1.5], sType='float32')
+]
+nco.ncatted(input="in.nc", options=opt)
+```
+
+#### `Value`
+
+Can be a single value or a list (or any python iterable type or a numpy array).
+
+*  If sType **is not** included then the type is inferred from the first value in the list
+*  If sType **is** included then any values in the list are **not** of sType are converted to the sType
+
+#### `sType`
+
+You can use the following: `f, d, l/i, s, b, ub, us, u, ll, ull`
+Or their numpy equivalents: `float32, float64, int32, int16, byte, ubyte, uint16, uint32, int64, uint64`
+
+For a netCDF3 character string use `c` or `char`
+For netCDF4 string(s) use `sng` or `string`
+
+#### `mode`
+
+For mode you can use the single character abbreviations as per `ncatted`: `a, c, d, m, n, o` or the following words: `a)ppend, create, delete, modify, overwrite`
+
+
+##  Limit and LimitSingle wrapper
+
+The following are equivalent:
+
+**nco**
+
+```bash
+ncks -d time,0,8,2 -d time,10 -d lat,-20.0,20.0 -d lon,50.0,350.0  -d lev,,,4
+```
+
+**pynco**
+
+```python
+opt = [
+    c.Limit("time", 0, 8, 2),
+    c.LimitSingle("time", 10),
+    c.Limit("lat", -20.0, 20.0),
+    c.Limit(dmn_name="lon", srt=50.0, end=350.0),
+    c.Limit(dmn_name="lev", srd=4)
+]
+
+nco.ncks(input="in.nc", output="out.nc", options=opt)
+```
+
+##  Rename wrapper
+
+The following are equivalent:
+
+**`nco`**
+
+```bash
+ncrename -v p,pressure -v t,temperature in.nc
+```
+
+**`pynco`**
+
+```python
+rDict = {
+    'p': 'pressure',
+    't': 'temperature'
+}
+nco.ncrename(input="in.nc", options=[ c.Rename("variable", rDict) ])
+```
+
+Also equivalent:
+
+**`nco`**
+
+```bash
+ncrename -d lon,longitude -d lat,latitude -v lon,longitude -v lat,latitude in.nc
+```
+
+**`pynco`**
+
+```python
+rDict = {
+    'lon': 'longitude',
+    'lat': 'latitude'
+}
+nco.ncrename(input="in.nc", options=[ c.Rename("d", rDict), c.Rename("v", rDict) ])
+```
+
 ## Support, Issues, Bugs, ...
 
 Please use the github page to report issues/bugs/features: https://github.com/nco/pynco.
@@ -116,7 +268,6 @@ For usage questions, please use [Stack Overflow](https://stackoverflow.com/quest
 
 `pynco` makes use of the GPLv2 License, see LICENSE.txt.
 
----
 
 ## Other stuff
 
diff --git a/nco/nco.py b/nco/nco.py
index a708e42..89f1b18 100644
--- a/nco/nco.py
+++ b/nco/nco.py
@@ -360,6 +360,8 @@ def version(self):
                                 stdout=subprocess.PIPE)
         ret = proc.communicate()
         ncra_help = ret[1]
+        if isinstance(ncra_help, bytes):
+            ncra_help = ncra_help.decode('utf-8')
         match = re.search('NCO netCDF Operators version (\d.*) ',
                           ncra_help)
         # some versions write version information in quotation marks
diff --git a/tests/conftest.py b/tests/conftest.py
index 8d50394..a2c67df 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -4,7 +4,6 @@
 import pytest
 import tempfile
 import numpy as np
-# import h5py
 import netCDF4
 import datetime
 from dateutil import relativedelta
@@ -37,7 +36,7 @@ def random_field():
 
 @pytest.fixture(scope="module")
 def mask4tests():
-    return np.random.random_integers(0, 1, (1, 5, 5))
+    return np.random.randint(1, size=(1, 5, 5))
 
 
 @pytest.fixture(scope="module")
@@ -47,15 +46,19 @@ def random_masked_field(mask4tests):
     return field
 
 
-# @pytest.fixture(scope="module")
-# def hdf_file(random_field, tempsrcdir):
-#     filename = os.path.join(tempsrcdir, 'testhdf.hdf5')
-#     f = h5py.File(filename, 'w')
-#     shape = random_field.shape
-#     dset = f.create_dataset("random_field", shape, dtype='f')
-#     dset[:, :] = random_field
-#     f.close()
-#     return filename
+@pytest.fixture(scope="module")
+def hdf_file(random_field, tempsrcdir):
+    try:
+        import h5py
+        filename = os.path.join(tempsrcdir, 'testhdf.hdf5')
+        f = h5py.File(filename, 'w')
+        shape = random_field.shape
+        dset = f.create_dataset("random_field", shape, dtype='f')
+        dset[:, :] = random_field
+        f.close()
+        return filename
+    except (ImportError, AttributeError):
+        return None
 
 
 @pytest.fixture(scope="module")
@@ -154,12 +157,12 @@ def testfiles8589(random_field, tempsrcdir):
         shape = random_field.shape
         f.createDimension('dim0', shape[0])
         f.createDimension('dim1', shape[1])
-        time = f.createDimension('time', 1)
+        f.createDimension('time')
         var = f.createVariable('random', 'f8', ('time', 'dim0', 'dim1',))
         time = f.createVariable('time', 'f8', ('time'))
         time.units = stdtimeunits
         time.calendar = noleapcalendar
-        var[:, :, :] = random_field
+        var[0, :, :] = random_field
         time[:] = netCDF4.date2num(date, stdtimeunits,
                                    calendar=noleapcalendar)
         f.close()
diff --git a/tests/test_nco.py b/tests/test_nco.py
index bb88b0a..63a243a 100644
--- a/tests/test_nco.py
+++ b/tests/test_nco.py
@@ -86,10 +86,10 @@ def test_use_list_inputs(foo_nc, bar_nc):
 def test_use_list_options(foo_nc):
     nco = Nco(debug=True)
     options = []
-    options.extend(['-a', 'units,time,o,c,days since 1999-01-01'])
+    options.extend(['-a', 'units,time,o,c,"days since 1999-01-01"'])
     options.extend(['-a', 'long_name,time,o,c,time'])
     options.extend(['-a', 'calendar,time,o,c,noleap'])
-    nco.ncrcat(input=foo_nc, output='out.nc', options=options)
+    nco.ncatted(input=foo_nc, output='out.nc', options=options)
 
 
 @pytest.mark.usefixtures("foo_nc", "bar_nc")
diff --git a/tests/test_nco_examples.py b/tests/test_nco_examples.py
index 508c8d7..51b6bd9 100644
--- a/tests/test_nco_examples.py
+++ b/tests/test_nco_examples.py
@@ -34,6 +34,8 @@ def test_ncks_hdf2nc(hdf_file):
     ncks        fl.hdf fl.nc # Convert HDF4->netCDF4 (NCO 4.4.0+, netCDF4.3.1+)
     ncks --hdf4 fl.hdf fl.nc # Convert HDF4->netCDF4 (NCO 4.3.7-4.3.9)
     """
+    if hdf_file is None:
+        pytest.skip('Skipped because h5py is not installed')
     nco = Nco(debug=True)
     nco.ncks(input=hdf_file, output='foo.nc')
     nco.ncks(input=hdf_file, output='foo.nc', hdf4=True)
@@ -51,11 +53,13 @@ def test_ncks_hdf2nc3(hdf_file):
     ncks --hdf4 -3 fl.hdf fl.nc # HDF4->netCDF3 (netCDF 4.3.0-)
     ncks --hdf4 -7 fl.hdf fl.nc # HDF4->netCDF4 classic (netCDF 4.3.0-)
     """
+    if hdf_file is None:
+        pytest.skip('Skipped because h5py is not installed')
     nco = Nco(debug=True)
-    nco.ncks(input=hdf_file, output='foo.nc', options='-3')
-    nco.ncks(input=hdf_file, output='foo.nc', options='-7 -L 1')
-    nco.ncks(input=hdf_file, output='foo.nc', options='-3', hdf4=True)
-    nco.ncks(input=hdf_file, output='foo.nc', options='-7', hdf4=True)
+    nco.ncks(input=hdf_file, output='foo.nc', options=['-3'])
+    nco.ncks(input=hdf_file, output='foo.nc', options=['-7 -L 1'])
+    nco.ncks(input=hdf_file, output='foo.nc', options=['-3'], hdf4=True)
+    nco.ncks(input=hdf_file, output='foo.nc', options=['-7'], hdf4=True)
 
 
 def test_temp_output_files(foo_nc):
@@ -116,9 +120,9 @@ def test_command_line_options(foo_nc):
     ncks --dbg_lvl 3 in.nc # Long option, alternate form
     """
     nco = Nco(debug=True)
-    nco.ncks(input=foo_nc, options='-D 3')
-    nco.ncks(input=foo_nc, options='--dbg_lvl=3')
-    nco.ncks(input=foo_nc, options='--dbg_lvl 3')
+    nco.ncks(input=foo_nc, options=['-D 3'])
+    nco.ncks(input=foo_nc, options=['--dbg_lvl=3'])
+    nco.ncks(input=foo_nc, options=['--dbg_lvl 3'])
     nco.ncks(input=foo_nc, dbg_lvl=3)
 
 
@@ -131,13 +135,16 @@ def test_specifying_input_files(testfiles8589):
     ncra -p input-path 85.nc 86.nc 87.nc 88.nc 89.nc 8589.nc
     ncra -n 5,2,1 85.nc 8589.nc
     """
-    inputs = ['85.nc', '86.nc', '87.nc', '88.nc', '89.nc']
     nco = Nco(debug=True)
-    nco.ncra(input=inputs, ouptut='8589.nc')
-    nco.ncra(input='8[56789].nc', ouptut='8589.nc')
-    srcdir = os.path.split(inputs[0])
-    nco.ncra(input=inputs, ouptut='8589.nc', path=srcdir)
-    nco.ncra(input=inputs, ouptut='8589.nc', nintap='5,2,1')
+    nco.ncra(input=testfiles8589, output='8589.nc')
+    nco.ncra(input=testfiles8589, output='8589.nc', nintap='5,2,1')
+
+    srcdir = os.path.dirname(testfiles8589[0])
+    basenames = [ os.path.basename(x) for x in testfiles8589 ]
+    nco.ncra(input=basenames, output='8589.nc', path=srcdir)
+
+    regpath = os.path.join(srcdir, '8[56789].nc')
+    nco.ncra(input=regpath, output='8589.nc')
 
 
 def test_determining_file_format(foo3c, foo364, foo4c, hdf_file):
@@ -156,12 +163,14 @@ def test_determining_file_format(foo3c, foo364, foo4c, hdf_file):
     nco.ncks(input=foo3c, options=['-M'])
     nco.ncks(input=foo364, options=['-M'])
     nco.ncks(input=foo4c, options=['-M'])
-    assert os.path.isfile(hdf_file)
-    nco.ncks(input=hdf_file, options=['-D 2 -M'])
-    # nco.ncks(input='http://thredds-test.ucar.edu/thredds/dodsC/testdods/in.nc',
-    #          options='-D 2 -M') # does not work from command line either
     nco.ncks(input=foo4c, options=['-D 2 -M'])
 
+    if hdf_file is not None:
+        assert os.path.isfile(hdf_file)
+        nco.ncks(input=hdf_file, options=['-D 2 -M'])
+    # nco.ncks(input='http://thredds-test.ucar.edu/thredds/dodsC/testdods/in.nc',
+    #          options=['-D 2', '-M']) # does not work from command line either
+
 
 def test_file_conversion(foo3c, foo4c):
     """
@@ -185,14 +194,14 @@ def test_file_conversion(foo3c, foo4c):
     nco.ncks(input=foo4c, output='foo_364.nc', fl_fmt='64bit')
     nco.ncks(input=foo3c, output='foo_4c.nc', fl_fmt='netcdf4_classic')
     nco.ncks(input=foo3c, output='foo_4.nc', fl_fmt='netcdf4')
-    nco.ncks(input=foo4c, output='foo_3c.nc', options='-3')
-    nco.ncks(input=foo4c, output='foo_3c.nc', options='--3')
-    nco.ncks(input=foo3c, output='foo_364c.nc', options='-6')
-    nco.ncks(input=foo3c, output='foo_364c.nc', options='--64')
-    nco.ncks(input=foo3c, output='foo_4.nc', options='-4')
-    nco.ncks(input=foo3c, output='foo_4.nc', options='--4')
-    nco.ncks(input=foo3c, output='foo_4c.nc', options='-7')
-    nco.ncks(input=foo3c, output='foo_4c.nc', options='--7')
+    nco.ncks(input=foo4c, output='foo_3c.nc', options=['-3'])
+    nco.ncks(input=foo4c, output='foo_3c.nc', options=['--3'])
+    nco.ncks(input=foo3c, output='foo_364c.nc', options=['-6'])
+    nco.ncks(input=foo3c, output='foo_364c.nc', options=['--64bit_offset'])
+    nco.ncks(input=foo3c, output='foo_4.nc', options=['-4'])
+    nco.ncks(input=foo3c, output='foo_4.nc', options=['--4'])
+    nco.ncks(input=foo3c, output='foo_4c.nc', options=['-7'])
+    nco.ncks(input=foo3c, output='foo_4c.nc', options=['--7'])
 
 
 def test_hyperslabs(testfileglobal):