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Implement confidence conversion scales

stix2.1
Emmanuelle Vargas-Gonzalez 2017-10-09 07:22:19 -04:00
parent 50f3d60259
commit 2ec8205f1e
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stix2/confidence/__init__.py Normal file
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"""
Functions to operate with STIX 2 Confidence scales.
"""

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stix2/confidence/scales.py Normal file
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"""Functions to perform conversions between the different Confidence scales.
As specified in STIX™ Version 2.1. Part 1: STIX Core Concepts - Appendix B"""
def none_low_med_high_to_value(scale_value):
"""
This method will transform a string value from the None / Low / Med /
High scale to its confidence integer representation.
Notes:
The scale for this confidence representation is the following.
"None" -> 0
"Low" -> 15
"Med" -> 50
"High" -> 85
Args:
scale_value: A string value from the scale. Accepted strings are
"None", "Low", "Med" and "High". Argument is case sensitive.
Returns:
int: The numerical representation corresponding to values in the None /
Low / Med / High scale.
Raises:
ValueError: If `scale_value` is not within the accepted strings.
"""
if scale_value == "None":
return 0
elif scale_value == "Low":
return 15
elif scale_value == "Med":
return 50
elif scale_value == "High":
return 85
else:
raise ValueError("STIX Confidence value cannot be determined for %s" % scale_value)
def value_to_none_low_medium_high(confidence_value):
"""
This method will transform an integer value into the None / Low / Med /
High scale string representation.
Notes:
The scale for this confidence representation is the following.
0 -> "None"
1-29 -> "Low"
30-69 -> "Med"
70-100 -> "High"
Args:
confidence_value: An integer value between 0 and 100.
Returns:
str: A string corresponding to the None / Low / Med / High scale.
Raises:
ValueError: If `confidence_value` is out of bounds.
"""
if confidence_value == 0:
return "None"
elif 29 >= confidence_value >= 1:
return "Low"
elif 69 >= confidence_value >= 30:
return "Med"
elif 100 >= confidence_value >= 70:
return "High"
else:
raise ValueError("Range of values out of bounds: %s" % confidence_value)
def zero_ten_to_value(scale_value):
"""
This method will transform a string value from the 0-10 scale to its
confidence integer representation.
Notes:
The scale for this confidence representation is the following.
"0" -> 0
"1" -> 10
"2" -> 20
"3" -> 30
"4" -> 40
"5" -> 50
"6" -> 60
"7" -> 70
"8" -> 80
"9" -> 90
"10" -> 100
Args:
scale_value: A string value from the scale. Accepted strings are "0"
through "10" inclusive.
Returns:
int: The numerical representation corresponding to values in the 0-10
scale.
Raises:
ValueError: If `scale_value` is not within the accepted strings.
"""
if scale_value == "0":
return 0
elif scale_value == "1":
return 10
elif scale_value == "2":
return 20
elif scale_value == "3":
return 30
elif scale_value == "4":
return 40
elif scale_value == "5":
return 50
elif scale_value == "6":
return 60
elif scale_value == "7":
return 70
elif scale_value == "8":
return 80
elif scale_value == "9":
return 90
elif scale_value == "10":
return 100
else:
raise ValueError("STIX Confidence value cannot be determined for %s" % scale_value)
def value_to_zero_ten(confidence_value):
"""
This method will transform an integer value into the 0-10 scale string
representation.
Notes:
The scale for this confidence representation is the following.
0-4 -> "0"
5-14 -> "1"
15-24 -> "2"
25-34 -> "3"
35-44 -> "4"
45-54 -> "5"
55-64 -> "6"
65-74 -> "7"
75-84 -> "8"
85-94 -> "9"
95-100 -> "10"
Args:
confidence_value: An integer value between 0 and 100.
Returns:
str: A string corresponding to the 0-10 scale.
Raises:
ValueError: If `confidence_value` is out of bounds.
"""
if 4 >= confidence_value >= 0:
return "0"
elif 14 >= confidence_value >= 5:
return "1"
elif 24 >= confidence_value >= 15:
return "2"
elif 34 >= confidence_value >= 25:
return "3"
elif 44 >= confidence_value >= 35:
return "4"
elif 54 >= confidence_value >= 45:
return "5"
elif 64 >= confidence_value >= 55:
return "6"
elif 74 >= confidence_value >= 65:
return "7"
elif 84 >= confidence_value >= 75:
return "8"
elif 94 >= confidence_value >= 85:
return "9"
elif 100 >= confidence_value >= 95:
return "10"
else:
raise ValueError("Range of values out of bounds: %s" % confidence_value)
def admiralty_credibility_to_value(scale_value):
"""
This method will transform a string value from the Admiralty Credibility
scale to its confidence integer representation.
Notes:
The scale for this confidence representation is the following.
"6 - Truth cannot be judged" -> N/A
"5 - Improbable" -> 10
"4 - Doubtful" -> 30
"3 - Possibly True" -> 50
"2 - Probably True" -> 70
"1 - Confirmed by other sources" -> 90
Args:
scale_value: A string value from the scale. Accepted strings are
"6 - Truth cannot be judged", "5 - Improbable", "4 - Doubtful",
"3 - Possibly True", "2 - Probably True" and
"1 - Confirmed by other sources". Argument is case sensitive.
Returns:
int: The numerical representation corresponding to values in the
Admiralty Credibility scale.
Raises:
ValueError: If `scale_value` is not within the accepted strings.
"""
if scale_value == "6 - Truth cannot be judged":
pass # TODO: Ask what happens here!
elif scale_value == "5 - Improbable":
return 10
elif scale_value == "4 - Doubtful":
return 30
elif scale_value == "3 - Possibly True":
return 50
elif scale_value == "2 - Probably True":
return 70
elif scale_value == "1 - Confirmed by other sources":
return 90
else:
raise ValueError("STIX Confidence value cannot be determined for %s" % scale_value)
def value_to_admiralty_credibility(confidence_value):
"""
This method will transform an integer value into the Admiralty Credibility
scale string representation.
Notes:
The scale for this confidence representation is the following.
N/A -> "6 - Truth cannot be judged"
0-19 -> "5 - Improbable"
20-39 -> "4 - Doubtful"
40-59 -> "3 - Possibly True"
60-79 -> "2 - Probably True"
80-100 -> "1 - Confirmed by other sources"
Args:
confidence_value: An integer value between 0 and 100.
Returns:
str: A string corresponding to the Admiralty Credibility scale.
Raises:
ValueError: If `confidence_value` is out of bounds.
"""
# TODO: Ask what happens with "6 - Truth cannot be judged" !
if 19 >= confidence_value >= 0:
return "5 - Improbable"
elif 39 >= confidence_value >= 20:
return "4 - Doubtful"
elif 59 >= confidence_value >= 40:
return "3 - Possibly True"
elif 79 >= confidence_value >= 60:
return "2 - Probably True"
elif 100 >= confidence_value >= 80:
return "1 - Confirmed by other sources"
else:
raise ValueError("Range of values out of bounds: %s" % confidence_value)
def wep_to_value(scale_value):
"""
This method will transform a string value from the WEP scale to its
confidence integer representation.
Notes:
The scale for this confidence representation is the following.
"Impossible" -> 0
"Highly Unlikely/Almost Certainly Not" -> 10
"Unlikely/Probably Not" -> 20
"Even Chance" -> 50
"Likely/Probable" -> 70
"Highly likely/Almost Certain" -> 90
"Certain" -> 100
Args:
scale_value: A string value from the scale. Accepted strings are
"Impossible", "Highly Unlikely/Almost Certainly Not",
"Unlikely/Probably Not", "Even Chance", "Likely/Probable",
"Highly likely/Almost Certain" and "Certain". Argument is case
sensitive.
Returns:
int: The numerical representation corresponding to values in the WEP
scale.
Raises:
ValueError: If `scale_value` is not within the accepted strings.
"""
if scale_value == "Impossible":
return 0
elif scale_value == "Highly Unlikely/Almost Certainly Not":
return 10
elif scale_value == "Unlikely/Probably Not":
return 30
elif scale_value == "Even Chance":
return 50
elif scale_value == "Likely/Probable":
return 70
elif scale_value == "Highly likely/Almost Certain":
return 90
elif scale_value == "Certain":
return 100
else:
raise ValueError("STIX Confidence value cannot be determined for %s" % scale_value)
def value_to_wep(confidence_value):
"""
This method will transform an integer value into the WEP scale string
representation.
Notes:
The scale for this confidence representation is the following.
0 -> "Impossible"
1-19 -> "Highly Unlikely/Almost Certainly Not"
20-39 -> "Unlikely/Probably Not"
40-59 -> "Even Chance"
60-79 -> "Likely/Probable"
80-99 -> "Highly likely/Almost Certain"
100 -> "Certain"
Args:
confidence_value: An integer value between 0 and 100.
Returns:
str: A string corresponding to the WEP scale.
Raises:
ValueError: If `confidence_value` is out of bounds.
"""
if confidence_value == 0:
return "Impossible"
elif 19 >= confidence_value >= 1:
return "Highly Unlikely/Almost Certainly Not"
elif 39 >= confidence_value >= 20:
return "Unlikely/Probably Not"
elif 59 >= confidence_value >= 40:
return "Even Chance"
elif 79 >= confidence_value >= 60:
return "Likely/Probable"
elif 99 >= confidence_value >= 80:
return "Highly likely/Almost Certain"
elif confidence_value == 100:
return "Certain"
else:
raise ValueError("Range of values out of bounds: %s" % confidence_value)
def dni_to_value(scale_value):
"""
This method will transform a string value from the DNI scale to its
confidence integer representation.
Notes:
The scale for this confidence representation is the following.
"Almost No Chance / Remote" -> 5
"Very Unlikely / Highly Improbable" -> 15
"Unlikely / Improbable" -> 30
"Roughly Even Change / Roughly Even Odds" -> 50
"Likely / Probable" -> 70
"Very Likely / Highly Probable" -> 85
"Almost Certain / Nearly Certain" -> 95
Args:
scale_value: A string value from the scale. Accepted strings are
"Almost No Chance / Remote", "Very Unlikely / Highly Improbable",
"Unlikely / Improbable", "Roughly Even Change / Roughly Even Odds",
"Likely / Probable", "Very Likely / Highly Probable" and
"Almost Certain / Nearly Certain". Argument is case sensitive.
Returns:
int: The numerical representation corresponding to values in the DNI
scale.
Raises:
ValueError: If `scale_value` is not within the accepted strings.
"""
if scale_value == "Almost No Chance / Remote":
return 5
elif scale_value == "Very Unlikely / Highly Improbable":
return 15
elif scale_value == "Unlikely / Improbable":
return 30
elif scale_value == "Roughly Even Change / Roughly Even Odds":
return 50
elif scale_value == "Likely / Probable":
return 70
elif scale_value == "Very Likely / Highly Probable":
return 85
elif scale_value == "Almost Certain / Nearly Certain":
return 95
else:
raise ValueError("STIX Confidence value cannot be determined for %s" % scale_value)
def value_to_dni(confidence_value):
"""
This method will transform an integer value into the DNI scale string
representation.
Notes:
The scale for this confidence representation is the following.
0-9 -> "Almost No Chance / Remote"
10-19 -> "Very Unlikely / Highly Improbable"
20-39 -> "Unlikely / Improbable"
40-59 -> "Roughly Even Change / Roughly Even Odds"
60-79 -> "Likely / Probable"
80-89 -> "Very Likely / Highly Probable"
90-100 -> "Almost Certain / Nearly Certain"
Args:
confidence_value: An integer value between 0 and 100.
Returns:
str: A string corresponding to the DNI scale.
Raises:
ValueError: If `confidence_value` is out of bounds.
"""
if 9 >= confidence_value >= 0:
return "Almost No Chance / Remote"
elif 19 >= confidence_value >= 10:
return "Very Unlikely / Highly Improbable"
elif 39 >= confidence_value >= 20:
return "Unlikely / Improbable"
elif 59 >= confidence_value >= 40:
return "Roughly Even Change / Roughly Even Odds"
elif 79 >= confidence_value >= 60:
return "Likely / Probable"
elif 89 >= confidence_value >= 80:
return "Very Likely / Highly Probable"
elif 100 >= confidence_value >= 90:
return "Almost Certain / Nearly Certain"
else:
raise ValueError("Range of values out of bounds: %s" % confidence_value)