Changeset 2611

Timestamp:

07/31/12 15:51:18 (12 years ago)

Author:

Kana Sugimoto

Message:

New Development: Yes

JIRA Issue: Yes (CAS-2820/Trac-277)

Ready for Test: Yes

Interface Changes: Yes

What Interface Changed: a new method, scantable.parse_idx_selection(mode, expr)

Test Programs: comming soon

Put in Release Notes: No

Module(s): scantable and CASA SD tasks

Description:

Added a new method, scantable.parse_idx_selection(mode, expr), in scantable class
to enable CASA type selection syntax of SCANNO, IFNO, POLNO, BEAMNO and row IDs
in scantable.
This method parses a comma separated selection expression (expr) in a string to
a list of IDs to set to selector. Index ranges in scantable are taken into account
when parsing.
Available modes are, 'scan' (parses SCANNO selection),
'if' (prases IFNO selection), 'pol' (parses POLNO selection), 'beam' (parses BEAMNO
selection), and 'row' (parses row id selction).

Usage:
stab = asap.scantable("SCANTABLE_NAME")
stab.scannos()
# assume this returns successive numbers from 2 to 20.
scanlist = stab.parse_idx_selection("scan","<5,10~13,>18")
# returns [2,3,4, 10,11,12,13, 19,20]
stab.set_selection(scans=scanlist)

Also made "<=" and ">=" available in scantable._parse_selection().

File:

• trunk/python/scantable.py (modified) (8 diffs)

trunk/python/scantable.py

@@ -1490 +1490 @@
         if not isinstance(maskstring,str):
             asaplog.post()
-            asaplog.push("Invalid mask expression")
+            asaplog.push("Mask expression should be a string.")
             asaplog.post("ERROR")
         
@@ -1498 +1498 @@
         if maskstring == "":
             maskstring = str(valid_ifs)[1:-1]
-        ## split each selection
+        ## split each selection "IF range[:CHAN range]"
         sellist = maskstring.split(',')
         for currselstr in sellist:
@@ -1504 +1504 @@
             # spw and mask string (may include ~, < or >)
             spwmasklist = self._parse_selection(selset[0], typestr='integer',
-                                                offset=1, minval=min(valid_ifs),
+                                                minval=min(valid_ifs),
                                                 maxval=max(valid_ifs))
             for spwlist in spwmasklist:
@@ -1602 +1602 @@
         return seldict
 
+    @asaplog_post_dec
+    def parse_idx_selection(self, mode, selexpr):
+        """
+        Parse CASA type mask selection syntax of SCANNO, IFNO, POLNO,
+        BEAMNO, and row number
+
+        Parameters:
+            mode       : which column to select.
+                         ['scan',|'if'|'pol'|'beam'|'row']
+            selexpr    : A comma separated selection expression.
+                     examples:
+                         ''          = all (returns [])
+                         '<2,4~6,9'  = indices less than 2, 4 to 6 and 9
+                                       (returns [0,1,4,5,6,9])
+        Returns:
+        A List of selected indices
+        """
+        if selexpr == "":
+            return []
+        valid_modes = {'s': 'scan', 'i': 'if', 'p': 'pol',
+                       'b': 'beam', 'r': 'row'}
+        smode =  mode.lower()[0]
+        if not (smode in valid_modes.keys()):
+            msg = "Invalid mode '%s'. Valid modes are %s" %\
+                  (mode, str(valid_modes.values()))
+            asaplog.post()
+            asaplog.push(msg)
+            asaplog.post("ERROR")
+        mode = valid_modes[smode]
+        minidx = None
+        maxidx = None
+        if smode == 'r':
+            minidx = 0
+            maxidx = self.nrow()
+        else:
+            idx = getattr(self,"get"+mode+"nos")()
+            minidx = min(idx)
+            maxidx = max(idx)
+            del idx
+        sellist = selexpr.split(',')
+        idxlist = []
+        for currselstr in sellist:
+            # single range (may include ~, < or >)
+            currlist = self._parse_selection(currselstr, typestr='integer',
+                                             minval=minidx,maxval=maxidx)
+            for thelist in currlist:
+                idxlist += range(thelist[0],thelist[1]+1)
+        msg = "Selected %s: %s" % (mode.upper()+"NO", str(idxlist))
+        asaplog.push(msg)
+        return idxlist
+
     def _parse_selection(self, selstr, typestr='float', offset=0.,
                          minval=None, maxval=None):
@@ -1611 +1662 @@
             offset :    The offset value to subtract from or add to
                         the boundary value if the selection string
-                        includes '<' or '>'
+                        includes '<' or '>' [Valid only for typestr='float']
             minval, maxval :  The minimum/maximum values to set if the
                               selection string includes '<' or '>'.
@@ -1618 +1669 @@
             A list of min/max pair of selections.
         Example:
-            _parseSelection('<3;5~7;9',typestr='int',offset=1,minval=0)
-            returns [[0,2],[5,7],[9,9]]
+            _parse_selection('<3;5~7;9',typestr='int',minval=0)
+            --> returns [[0,2],[5,7],[9,9]]
+            _parse_selection('<3;5~7;9',typestr='float',offset=0.5,minval=0)
+            --> returns [[0.,2.5],[5.0,7.0],[9.,9.]]
         """
         selgroups = selstr.split(';')
@@ -1625 +1678 @@
         if typestr.lower().startswith('int'):
             formatfunc = int
+            offset = 1
         else:
             formatfunc = float
@@ -1630 +1684 @@
         for currsel in  selgroups:
             if currsel.find('~') > 0:
+                # val0 <= x <= val1
                 minsel = formatfunc(currsel.split('~')[0].strip())
                 maxsel = formatfunc(currsel.split('~')[1].strip()) 
-            elif currsel.strip().startswith('<'):
-                minsel = minval
-                maxsel = formatfunc(currsel.split('<')[1].strip()) \
-                         - formatfunc(offset)
-            elif currsel.strip().startswith('>'):
-                minsel = formatfunc(currsel.split('>')[1].strip()) \
+            elif currsel.strip().find('<=') > -1:
+                bound = currsel.split('<=')
+                try: # try "x <= val"
+                    minsel = minval
+                    maxsel = formatfunc(bound[1].strip())
+                except ValueError: # now "val <= x"
+                    minsel = formatfunc(bound[0].strip())
+                    maxsel = maxval
+            elif currsel.strip().find('>=') > -1:
+                bound = currsel.split('>=')
+                try: # try "x >= val"
+                    minsel = formatfunc(bound[1].strip())
+                    maxsel = maxval
+                except ValueError: # now "val >= x"
+                    minsel = minval
+                    maxsel = formatfunc(bound[0].strip())
+            elif currsel.strip().find('<') > -1:
+                bound = currsel.split('<')
+                try: # try "x < val"
+                    minsel = minval
+                    maxsel = formatfunc(bound[1].strip()) \
+                             - formatfunc(offset)
+                except ValueError: # now "val < x"
+                    minsel = formatfunc(bound[0].strip()) \
                          + formatfunc(offset)
-                maxsel = maxval
+                    maxsel = maxval
+            elif currsel.strip().find('>') > -1:
+                bound = currsel.split('>')
+                try: # try "x > val"
+                    minsel = formatfunc(bound[1].strip()) \
+                             + formatfunc(offset)
+                    maxsel = maxval
+                except ValueError: # now "val > x"
+                    minsel = minval
+                    maxsel = formatfunc(bound[0].strip()) \
+                             - formatfunc(offset)
             else:
                 minsel = formatfunc(currsel)