Added fetch_input.py

Tools/fetch_input.py

+#!/usr/bin/python
+
+# File: fetch_input.py
+
+from __future__ import print_function
+import sys
+import os
+import yaml
+import json
+
+def open_and_parse_file(fileName) :
+    """Opens a file and parses it using the YAML sintax 
+
+    :param fileName: name of the file
+    :type fileName: ``string``
+    :return: parsed data
+    :rtype: ``dict``
+
+    """
+    data = {}
+    try : 
+       with open(fileName, 'r') as stream:
+           try:
+              data = yaml.load(stream,Loader=yaml.SafeLoader)
+           except:
+              print("Cannot parse file")
+    except : 
+       print("Cannot open file : ",fileName)
+    return data
+
+def check_data(keyword, parsed_data, default) : 
+    #
+    data = {}
+    #
+    if keyword in parsed_data.keys() : 
+       for key in default.keys() : 
+          if key in parsed_data[keyword].keys() : 
+             data[key] = parsed_data[keyword][key]
+          else : 
+             data[key] = default[key]
+    else : 
+       print("Missing keyword in input file : ",keyword)
+    return data
+
+def read_input_west(*args, **kwargs):
+    #
+    fileName = args[0]
+    #
+    default = {}
+    default["qe_prefix"] = "pwscf"
+    default["west_prefix"] = "west"
+    default["outdir"] = "./"
+    #
+    parsed_data = open_and_parse_file(fileName)
+    #
+    checked_data = check_data( "input_west", parsed_data, default )
+    print( checked_data )
+    return checked_data
+
+def read_wstat_control(*args, **kwargs):
+    #
+    fileName = args[0]
+    nq = args[1]
+    #
+    default = {}
+    default["wstat_calculation"] = "S"
+    default["n_pdep_eigen"] = 1
+    default["n_pdep_times"] = 4
+    default["n_pdep_maxiter"] = 100
+    default["n_dfpt_maxiter"] = 250
+    default["n_pdep_read_from_file"] = 0
+    default["trev_pdep"] = 1.e-3
+    default["trev_pdep_rel"] = 1.e-1
+    default["tr2_dfpt"] = 1.e-12
+    default["l_kinetic_only"] = False
+    default["l_minimize_exx_if_active"] = False
+    default["l_use_ecutrho"] = False
+    default["qlist"] = [ i+1 for i in range(nq) ]
+    #
+    parsed_data = open_and_parse_file(fileName)
+    #
+    checked_data = check_data( "wstat_control", parsed_data, default )
+    print( checked_data )
+    return checked_data