sage.features.four_ti_2: New, use it in sage.interfaces.four_ti_2, sa…

…ge.sandpiles

src/sage/features/four_ti_2.py

@@ -0,0 +1,13 @@
+from sage.env import SAGE_ENV
+
+from sage.features import Executable
+
+class FourTi2Executable(Executable):
+    r"""
+    Feature for the 4ti2 executables.
+    """
+    def __init__(self, name):
+        Executable.__init__(self,
+                            name="4ti2-" + name,
+                            executable=SAGE_ENV.get("FOURTITWO_" + name.upper(), None) or name,
+                            spkg="4ti2")

src/sage/interfaces/four_ti_2.py

@@ -36,6 +36,8 @@
 #*****************************************************************************
 
 from sage.rings.integer_ring import ZZ
+from sage.features.four_ti_2 import FourTi2Executable
+
 import os
 
 
@@ -271,7 +273,7 @@ def _process_input(self, kwds):
     # Commands #
     ############
 
-    def call(self, command, project, verbose=True):
+    def call(self, command, project, verbose=True, *, options=()):
         r"""
         Run the 4ti2 program ``command`` on the project named
         ``project`` in the directory ``directory()``.
@@ -281,6 +283,7 @@ def call(self, command, project, verbose=True):
         - command -- The 4ti2 program to run.
         - project -- The file name of the project to run on.
         - verbose -- Display the output of 4ti2 if ``True``.
+        - options -- A list of strings to pass to the program.
 
         EXAMPLES::
 
@@ -292,8 +295,11 @@ def call(self, command, project, verbose=True):
             [-5  3  0]
         """
         import subprocess
-
-        cmd = '%s %s' % (command, project)
+        feature = FourTi2Executable(command)
+        feature.require()
+        executable = feature.executable
+        options = " ".join(options)
+        cmd = f'{executable} {options} {project}'
         if verbose is False:
             cmd += " > /dev/null 2> /dev/null"
         subprocess.call(cmd, shell=True, cwd=self.directory())
@@ -326,7 +332,7 @@ def zsolve(self, mat=None, rel=None, rhs=None, sign=None, lat=None, project=None
 
         """
         project = self._process_input(locals())
-        self.call('zsolve -q', project)
+        self.call('zsolve', project, options=['-q'])
         return [self.read_matrix(project+'.'+ext) for ext in
                 ['zinhom', 'zhom', 'zfree']]
 
@@ -343,7 +349,7 @@ def qsolve(self, mat=None, rel=None, sign=None, project=None):
             [[], [ 1 -2  1]]
         """
         project = self._process_input(locals())
-        self.call('qsolve -q -parbitrary', project)
+        self.call('qsolve', project, options=['-q', '-parbitrary'])
         return [self.read_matrix(project+'.'+ext) for ext in
                 ['qhom', 'qfree']]
 
@@ -362,7 +368,7 @@ def rays(self, mat=None, project=None):
             [2 0 1 0 1 2 1 2 0]
         """
         project = self._process_input(locals())
-        self.call('rays -q -parbitrary', project)
+        self.call('rays', project, options=['-q', '-parbitrary'])
         return self.read_matrix(project+'.ray')
 
     def hilbert(self, mat=None, lat=None, project=None):
@@ -385,7 +391,7 @@ def hilbert(self, mat=None, lat=None, project=None):
             [1 1 1]
         """
         project = self._process_input(locals())
-        self.call('hilbert -q', project)
+        self.call('hilbert', project, options=['-q'])
         return self.read_matrix(project+'.hil')
 
     def graver(self, mat=None, lat=None, project=None):
@@ -409,7 +415,7 @@ def graver(self, mat=None, lat=None, project=None):
             [ 2  1  0]
         """
         project = self._process_input(locals())
-        self.call('graver -q', project)
+        self.call('graver', project, options=['-q'])
         return self.read_matrix(project+'.gra')
 
     def ppi(self, n):
@@ -428,7 +434,7 @@ def ppi(self, n):
             [ 1 -2  1]
 
         """
-        self.call('ppi 2> /dev/null', n)
+        self.call('ppi', f'{n} 2> /dev/null')
         return self.read_matrix('ppi%s.gra'%n)
 
     def circuits(self, mat=None, project=None):
@@ -445,7 +451,7 @@ def circuits(self, mat=None, project=None):
             [ 3  0 -1]
         """
         project = self._process_input(locals())
-        self.call('circuits -q -parbitrary', project)
+        self.call('circuits', project, options=['-q', '-parbitrary'])
         return self.read_matrix(project+'.cir')
 
     def minimize(self, mat=None, lat=None):
@@ -482,7 +488,7 @@ def groebner(self, mat=None, lat=None, project=None):
             [ 2  1  0]
         """
         project = self._process_input(locals())
-        self.call('groebner -q -parbitrary', project)
+        self.call('groebner', project, options=['-q', '-parbitrary'])
         return self.read_matrix(project+'.gro')
 
     def _magic3x3(self):

src/sage/sandpiles/sandpile.py

@@ -322,13 +322,11 @@
 
 from IPython.lib import pretty
 
-import os  # CHECK: possibly unnecessary after removing 4ti2-dependent methods
 from sage.calculus.functional import derivative
 from sage.combinat.integer_vector import integer_vectors_nk_fast_iter
 from sage.combinat.parking_functions import ParkingFunctions
 from sage.combinat.set_partition import SetPartitions
 from sage.combinat.vector_partition import IntegerVectorsIterator
-from sage.env import SAGE_LOCAL
 from sage.functions.log import exp
 from sage.functions.other import binomial
 from sage.geometry.polyhedron.constructor import Polyhedron
@@ -346,10 +344,7 @@
 from sage.rings.all import Integer, PolynomialRing, QQ, ZZ
 from sage.symbolic.constants import I, pi
 from sage.symbolic.ring import SR
-
-# TODO: remove the following line once 4ti2 functions are removed
-path_to_zsolve = os.path.join(SAGE_LOCAL, 'bin', 'zsolve')
-
+from sage.features.four_ti_2 import FourTi2Executable
 
 
 def _sandpile_help(cls, usage, verbose=True):
@@ -5122,8 +5117,6 @@ def _set_linear_system(self):
 
             This method requires 4ti2.
         """
-        # import os
-
         L = self._sandpile._laplacian.transpose()
         n = self._sandpile.num_verts()
 
@@ -5172,7 +5165,9 @@ def _set_linear_system(self):
             sign_file.write('\n')
         # compute
         try:
-            os.system(path_to_zsolve+' -q ' + lin_sys + ' > ' + lin_sys_log)
+            import os
+            path_to_zsolve = FourTi2Executable('zsolve').executable
+            os.system(path_to_zsolve + ' -q ' + lin_sys + ' > ' + lin_sys_log)
             # process the results
             zhom_file = open(lin_sys_zhom,'r')
         except IOError: