Author: Antonio Cuni <anto.c...@gmail.com>
Branch: extradoc
Changeset: r3729:0204e9f12006
Date: 2011-06-17 15:07 +0200
http://bitbucket.org/pypy/extradoc/changeset/0204e9f12006/
Log: more slides
diff --git a/talk/ep2011/talk/rational.c b/talk/ep2011/talk/rational.c
new file mode 100644
--- /dev/null
+++ b/talk/ep2011/talk/rational.c
@@ -0,0 +1,11 @@
+#include <stdio.h>
+
+int main()
+{
+ float px = 0.0, py = 0.0;
+ while (px < 2000.0) {
+ px += 1.0;
+ py += 0.5;
+ }
+ printf("%f %f\n", px, py);
+}
diff --git a/talk/ep2011/talk/rational.py b/talk/ep2011/talk/rational.py
new file mode 100644
--- /dev/null
+++ b/talk/ep2011/talk/rational.py
@@ -0,0 +1,21 @@
+class Point(object):
+
+ def __init__(self, x, y):
+ self.x = x
+ self.y = y
+
+ def __add__(self, other):
+ if not isinstance(other, Point):
+ raise TypeError
+ x1 = self.x + other.x
+ y1 = self.y + other.y
+ return Point(x1, y1)
+
+def main():
+ p = Point(0.0, 0.0)
+ while p.x < 2000.0:
+ p = p + Point(1.0, 0.5)
+ print p.x, p.y
+
+main()
+
diff --git a/talk/ep2011/talk/talk.rst b/talk/ep2011/talk/talk.rst
--- a/talk/ep2011/talk/talk.rst
+++ b/talk/ep2011/talk/talk.rst
@@ -223,4 +223,222 @@
:align: center
+Why Python is slow?
+-------------------
+- Huge stack of layers over the bare metal
+
+- Abstraction has a cost |pause| (... or not?) |pause|
+
+- XXX: write a nice diagram showing how far is "a+b" from "add EAX, EBX" (or
+ equivalent)
+
+
+Killing the abstraction overhead
+--------------------------------
+
+|scriptsize|
+|column1|
+|example<| Python |>|
+
+.. sourcecode:: python
+
+ class Point(object):
+
+ def __init__(self, x, y):
+ self.x = x
+ self.y = y
+
+ def __add__(self, q):
+ if not isinstance(q, Point):
+ raise TypeError
+ x1 = self.x + q.x
+ y1 = self.y + q.y
+ return Point(x1, y1)
+
+ def main():
+ p = Point(0.0, 0.0)
+ while p.x < 2000.0:
+ p = p + Point(1.0, 0.5)
+ print p.x, p.y
+
+|end_example|
+
+|pause|
+
+|column2|
+|example<| C |>|
+
+.. sourcecode:: c
+
+ #include <stdio.h>
+
+
+
+
+
+
+
+
+
+ int main() {
+ float px = 0.0, py = 0.0;
+ while (px < 2000.0) {
+ px += 1.0;
+ py += 0.5;
+ }
+ printf("%f %f\n", px, py);
+ }
+
+|end_example|
+|end_columns|
+|end_scriptsize|
+
+.. at this point, we show it in the jitviewer
+
+Useless optimization techniques
+-------------------------------
+
+.. XXX: I'm not sure how useful is this slide
+
+|scriptsize|
+
+|column1|
+|example<| |>|
+
+.. sourcecode:: python
+
+ #
+ for item in some_large_list:
+ self.meth(item)
+
+|end_example|
+|column2|
+|example<| |>|
+
+.. sourcecode:: python
+
+ meth = self.meth
+ for item in some_large_list:
+ meth(item)
+
+
+|end_example|
+|end_columns|
+
+|pause|
+
+|column1|
+|example<| |>|
+
+.. sourcecode:: python
+
+ def foo():
+ res = 0
+ for item in some_large_list:
+ res = res + abs(item)
+ return res
+
+|end_example|
+|column2|
+|example<| |>|
+
+.. sourcecode:: python
+
+ def foo(abs=abs):
+ res = 0
+ for item in some_large_list:
+ res = res + abs(item)
+ return res
+
+|end_example|
+|end_columns|
+
+|pause|
+
+|column1|
+|example<| |>|
+
+.. sourcecode:: python
+
+ #
+
+ [i**2 for i in range(100)]
+
+|end_example|
+|column2|
+|example<| |>|
+
+.. sourcecode:: python
+
+ from itertools import *
+ list(imap(pow, count(0),
+ repeat(2, 100)))
+
+|end_example|
+|end_columns|
+
+|pause|
+
+|column1|
+|example<| |>|
+
+.. sourcecode:: python
+
+ for i in range(large_number):
+ ...
+
+|end_example|
+|column2|
+|example<| |>|
+
+.. sourcecode:: python
+
+ for i in xrange(large_number):
+ ...
+
+|end_example|
+|end_columns|
+
+|pause|
+
+|column1|
+|example<| |>|
+
+.. sourcecode:: python
+
+ class A(object):
+ pass
+
+|end_example|
+|column2|
+|example<| |>|
+
+.. sourcecode:: python
+
+ class A(object):
+ __slots__ = ['a', 'b', 'c']
+
+|end_example|
+|end_columns|
+
+|end_scriptsize|
+
+
+Concrete example: ``ctypes``
+----------------------------
+
+|example<| |>|
+|scriptsize|
+
+.. sourcecode:: python
+
+ import ctypes
+ libm = ctypes.CDLL('libm.so')
+ pow = libm.pow
+ pow.argtypes = [ctypes.c_double, ctypes.c_double]
+ pow.restype = ctypes.c_double
+
+|end_scriptsize|
+|end_example|
+
_______________________________________________
pypy-commit mailing list
pypy-commit@python.org
http://mail.python.org/mailman/listinfo/pypy-commit
