Databases
StackOverflow2013
Postsdbo
POLoading a datalog program in a file into pyDatalog
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POLoading a datalog program in a file into pyDatalog
    primarykey
    data
    text
    <p>I am trying to use the pyDatalog.load() method to load a small pyDatalog program. For example, I am loading the factorial sample from <a href="https://sites.google.com/site/pydatalog/" rel="nofollow">https://sites.google.com/site/pydatalog/</a></p> <pre><code>from pyDatalog import pyDatalog pyDatalog.create_atoms('factorial, N, F') # gives datalog capability to these words def run_program(): N = pyDatalog.Variable() F = pyDatalog.Variable() file_in = open("sample_datalog_program.dl", 'r') mc = file_in.read() print mc @pyDatalog.program() def _(): # the function name is ignored pyDatalog.load(mc) #pyDatalog.load(""" #+ (factorial[1]==1) #(factorial[N] == F) &lt;= (N &gt; 1) &amp; (F == N*factorial[N-1]) #""") print(pyDatalog.ask('factorial[4]==F')) file_in.close() pass if __name__ == "__main__": run_program() </code></pre> <p>the file sample_datalog_program.dl contains the following:</p> <pre><code>""" + (factorial[1]==1) (factorial[N] == F) &lt;= (N &gt; 1) &amp; (F == N*factorial[N-1]) """ </code></pre> <p>What am I doing wrong? When I replace the line pyDatalog.load(mc) by the next 4 commented lines it works fine. </p> <p>The error I get is:</p> <pre><code> /usr/local/Cellar/python/2.7.3/Frameworks/Python.framework/Versions/2.7/bin/python2.7 run_datalog_program.py pyDatalog version 0.12.0 Traceback (most recent call last): File "run_datalog_program.py", line 25, in &lt;module&gt; run_program() File "run_datalog_program.py", line 11, in run_program @pyDatalog.program() File "/usr/local/lib/python2.7/site-packages/pyDatalog/pyParser.py", line 191, in add_program load(source_code, newglobals, defined, function=func_name) File "/usr/local/lib/python2.7/site-packages/pyDatalog/pyParser.py", line 154, in load six.exec_(code, newglobals) File "/usr/local/lib/python2.7/site-packages/six.py", line 308, in exec_ exec("""exec code in globs, locs""") File "&lt;string&gt;", line 1, in &lt;module&gt; File "_", line 1, in &lt;module&gt; File "/usr/local/lib/python2.7/site-packages/pyDatalog/pyDatalog.py", line 115, in load return pyParser.load(code) File "/usr/local/lib/python2.7/site-packages/pyDatalog/pyParser.py", line 133, in load spaces = r.match(line).group() TypeError: expected string or buffer """ + (factorial[1]==1) (factorial[N] == F) &lt;= (N &gt; 1) &amp; (F == N*factorial[N-1]) """ Process finished with exit code 1 </code></pre> <p>Thank you!</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USAnderson Green
    1. USAndres
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload