Prom Module "Conformance Checking of DPN" throws impossible exception

ahense

I took the XES-log below, applied the Alpha-Algorithm with standard settings to it and then module
"Conformance Checking of DPN" with standard settings on the Petrinet and the log. In this last step I corrected the default mapping to map D+complete to D and put End as a final marking.

I then got this:
"Failed to compute the empty trace alignment, Nested Exception: org.processmining.plugins.balancedconformance.controlflow.UnreliableControlFlowAlignmentException: Unreliable result after visiting 1 states, queueing 1 states. 0 data alignments cached, 0 cache hits for trace [], Reason: IMPOSSIBLE"

Is this a bug or is it a hidden message that something with my log or my Petrinet is wrong?







<?xml version="1.0" encoding="UTF-8" ?>
<!-- This file has been generated with the OpenXES library. It conforms -->
<!-- to the XML serialization of the XES standard for log storage and -->
<!-- management. -->
<!-- XES standard version: 1.0 -->
<!-- OpenXES library version: 1.0RC7 -->
<!-- OpenXES is available from http://www.openxes.org/ -->
<log xes.version="1.0" xes.features="nested-attributes" openxes.version="1.0RC7">
    <global scope="trace">
        <string key="concept:name" value="UNKNOWN"/>
    </global>
    <global scope="event">
        <date key="time:timestamp" value="1970-01-01T00:00:00.000+01:00"/>
        <string key="concept:name" value="UNKNOWN"/>
        <string key="lifecycle:transition" value="UNKNOWN"/>
        <string key="concept:instance" value="UNKNOWN"/>
    </global>
    <classifier name="Activity classifier" keys="concept:instance concept:name lifecycle:transition"/>
    <string key="concept:name" value="Merged Log"/>
    <trace>
        <string key="concept:name" value="405"/>
        <event>
            <int key="x" value="1"/>
            <string key="lifecycle:instance" value="405.1"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:35:07.122+01:00"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="lifecycle:instance" value="405.3"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:36:25.595+01:00"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="lifecycle:instance" value="405.2"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:36:32.229+01:00"/>
        </event>
        <event>
            <string key="lifecycle:instance" value="405.4"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:37:52.355+01:00"/>
            <boolean key="again" value="false"/>
        </event>
    </trace>
    <trace>
        <string key="concept:name" value="406"/>
        <event>
            <int key="x" value="1"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.1"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:35:30.932+01:00"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.3"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:36:46.737+01:00"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.2"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:36:51.404+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.4"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:38:01.506+01:00"/>
            <boolean key="again" value="true"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.5"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:39:04.815+01:00"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.7"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:39:46.103+01:00"/>
        </event>
        <event>
            <int key="x" value="1"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.6"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:39:49.280+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="406.8"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:40:39.098+01:00"/>
            <boolean key="again" value="false"/>
        </event>
    </trace>
    <trace>
        <string key="concept:name" value="407"/>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.1"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:35:41.210+01:00"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.3"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:36:58.059+01:00"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.2"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:37:02.094+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.4"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:38:09.548+01:00"/>
            <boolean key="again" value="true"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.5"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:39:11.160+01:00"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.6"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:39:56.812+01:00"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.7"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:40:01.049+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.8"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:40:44.395+01:00"/>
            <boolean key="again" value="true"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.9"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:41:03.936+01:00"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.11"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:41:28.034+01:00"/>
        </event>
        <event>
            <int key="x" value="2"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.10"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:41:31.392+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="407.12"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:42:13.778+01:00"/>
            <boolean key="again" value="false"/>
        </event>
    </trace>
    <trace>
        <string key="concept:name" value="408"/>
        <event>
            <int key="x" value="3"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="408.1"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:35:49.567+01:00"/>
        </event>
        <event>
            <int key="x" value="3"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="408.3"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:37:10.022+01:00"/>
        </event>
        <event>
            <int key="x" value="3"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="408.2"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:37:14.802+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="408.4"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:38:26.713+01:00"/>
            <boolean key="again" value="false"/>
        </event>
    </trace>
    <trace>
        <string key="concept:name" value="409"/>
        <event>
            <int key="x" value="4"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.1"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:35:56.017+01:00"/>
        </event>
        <event>
            <int key="x" value="4"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.2"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:37:22.422+01:00"/>
        </event>
        <event>
            <int key="x" value="4"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.3"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:37:25.531+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.4"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:38:46.755+01:00"/>
            <boolean key="again" value="true"/>
        </event>
        <event>
            <int key="x" value="4"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.5"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:39:18.239+01:00"/>
        </event>
        <event>
            <int key="x" value="4"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.6"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:40:08.830+01:00"/>
        </event>
        <event>
            <int key="x" value="4"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.7"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:40:11.914+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="409.8"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:40:51.638+01:00"/>
            <boolean key="again" value="false"/>
        </event>
    </trace>
    <trace>
        <string key="concept:name" value="410"/>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.1"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:36:03.801+01:00"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.3"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:37:30.991+01:00"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.2"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:37:35.938+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.4"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:38:53.957+01:00"/>
            <boolean key="again" value="true"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.5"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:39:37.962+01:00"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.7"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:40:16.230+01:00"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.6"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:40:19.655+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.8"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:40:58.237+01:00"/>
            <boolean key="again" value="true"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.9"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="A"/>
            <date key="time:timestamp" value="2017-01-31T09:41:10.746+01:00"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.11"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="C"/>
            <date key="time:timestamp" value="2017-01-31T09:41:37.418+01:00"/>
        </event>
        <event>
            <int key="x" value="5"/>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.10"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="B"/>
            <date key="time:timestamp" value="2017-01-31T09:41:41.265+01:00"/>
        </event>
        <event>
            <string key="org:resource" value="PA-1d65ff97-7ae9-40cd-b59e-c2605b1b6a9b"/>
            <string key="lifecycle:instance" value="410.12"/>
            <string key="lifecycle:transition" value="complete"/>
            <string key="concept:name" value="D"/>
            <date key="time:timestamp" value="2017-01-31T09:42:19.323+01:00"/>
            <boolean key="again" value="false"/>
        </event>
    </trace>
</log>

fmannhardt

I reproduced the problem using the current version of the package. However, the message is not an error. The alignment procedure found that it is is impossible to compute an alignment because the Petri net returned by the Alpha Algorithm is unbounded:

Transition '+D+complete' generates two tokens upon execution one in the 'sink' place and another one in the input place of '+A+complete'. There is no way to consume this extra token and reach the final marking ['snk'].

However, I will update the error message with a more understandable text. 3Since it is mostly caused by unsound Petri nets and not a programming error.

ahense

This answers my question. Thanks for pointing this out.