Changes between Version 23 and Version 24 of SwiggingHlsvd

Timestamp:

Jul 14, 2009, 4:58:51 PM (10 years ago)

Author:

flip

Comment:

--

SwiggingHlsvd

@@ -126 +126 @@
 
 Our Python call is just two lines of code, and could be one:
-::
-
-    root, fre, dam, amp, phase, sv, snoise, rms, nitf, ndiv = \
-        hlsvd(y, ndp, tstep, m, nssv, nit)
-
+}}}
+{{{
+!python
+
+root, fre, dam, amp, phase, sv, snoise, rms, nitf, ndiv = \
+    hlsvd(y, ndp, tstep, m, nssv, nit)
+}}}
+
+{{{
+#!rst
 
 With this Pythonic interface in mind, let's look at how the interfaces generated by SWIG and ctypes stack up. 
@@ -144 +149 @@
 The resulting code is something only a mother could love. I should point out that I think SWIG is near miraculous in what it can do, and I don't intend any of my snide comments as criticism of SWIG or its developers. It's just that autotranslated code has all the charm of autotranslated writing. If you've ever used Babelfish, you know what I'm talking about. Meaning is (usually) preserved, albeit crudely, but all the idioms are lost and it's eminently clear that the text (or in this case, the interface) was not created by a native speaker. 
 
-So we get ugly code like this (where inputs is a Python list I populated from a file):
-::
-
-    yr = hlsvd_wrapper.new_float_array(2048)
-    for i in range(0, 2048):
-        hlsvd_wrapper.float_array_setitem(yr, i, inputs[i])
-
-
+So we get ugly code like the example below (in which ``inputs`` is a Python list I populated from a file):
+}}}
+{{{
+#!python
+
+yr = hlsvd_wrapper.new_float_array(2048)
+for i in range(0, 2048):
+   hlsvd_wrapper.float_array_setitem(yr, i, inputs[i])
+}}}
+
+{{{
+#!rst
 And this (which I think is only necessary because of ``hlsvd()``'s pass-by-reference awkwardness I mentioned above):
-::
-
-   tstep = hlsvd_wrapper.new_tstep()
-   hlsvd_wrapper.tstep_assign(tstep, .256)
-
+}}}
+
+{{{
+#!python
+tstep = hlsvd_wrapper.new_tstep()
+hlsvd_wrapper.tstep_assign(tstep, .256)
+}}}
 
 And a series of calls like this one to create the output arrays:
-::
-
-   rootr = hlsvd_wrapper.new_double_array(50)
+
+{{{
+#!python
+rootr = hlsvd_wrapper.new_double_array(50)
+}}}
+
+{{{
+#!rst
 
 In all, here's what one has to do just to create (not populate) the variables to be used in the call to ``hlsvd()``:
-::
-
+}}}
+
+{{{
+#!python
     yr = hlsvd_wrapper.new_float_array(2048)
     yi = hlsvd_wrapper.new_float_array(2048)
@@ -186 +204 @@
     ndiv = hlsvd_wrapper.new_ndiv()
     nitf = hlsvd_wrapper.new_nitf()
-
+}}}
 
 The call itself looks like this:
-::
-
+
+{{{
+#!python
     hlsvd_wrapper.hlsvd(yr, yi, ndata, ndp, tstep, m, nssv, 
                          rootr, rooti, fre, dam, amp, phase, sv, snoise, 
                          rms, ndiv, nit, nitf)
-
+}}}
 
 Note that every disadvantage of the C interface remains. There's no distinction between input and output parameters. The complex numbers are still represented as correlated lists of floats. The list/array sizes must be specified explicitly, and an opportunity for memory corruption or a crash exists if one gets it wrong. One must keep track of which variables are floats and which are doubles. And it's many more lines of code than the Python version. (Some of this is exacerbated by ``hlsvd()``'s pass-by-reference interface.)