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rasbt 2014-04-22 13:30:30 -04:00
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benchmarks/timeit_tests.ipynb
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@ -1,7 +1,7 @@
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@ -18,6 +18,17 @@
"[Link to this IPython Notebook on GitHub](https://github.com/rasbt/python_reference/blob/master/benchmarks/timeit_tests.ipynb)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<hr>\n",
"I am really looking forward to your comments and suggestions to improve and extend this collection! Just send me a quick note \n",
"via Twitter: [@rasbt](https://twitter.com/rasbt) \n",
"or Email: [bluewoodtree@gmail.com](mailto:bluewoodtree@gmail.com)\n",
"<hr>"
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"cell_type": "markdown",
"metadata": {},
@ -37,6 +48,8 @@
" - [String reversing: [::-1] vs. `''.join(reversed())`](#str_reverse)\n",
" - [String concatenation: `+=` vs. `''.join()`](#string_concat)\n",
" - [Assembling strings](#string_assembly) \n",
" - [Testing if a string is an integer](#is_integer)\n",
" - [Testing if a string is a number](#is_number)\n",
"- [List operations](#list_operations)\n",
" - [List reversing: [::-1] vs. reverse() vs. reversed()](#list_reverse)\n",
" - [Creating lists using conditional statements](#create_cond_list)\n",
@ -229,6 +242,8 @@
"cell_type": "markdown",
"metadata": {},
"source": [
"<br>\n",
"<br>\n",
"<a name='string_assembly'></a>\n",
"## Assembling strings\n",
"\n",
@ -294,6 +309,161 @@
"cell_type": "markdown",
"metadata": {},
"source": [
"<br>\n",
"<br>\n",
"<a name='is_integer'></a>\n",
"## Testing if a string is an integer"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import timeit\n",
"\n",
"def string_is_int(a_str):\n",
" try:\n",
" int(a_str)\n",
" return True\n",
" except ValueError:\n",
" return False\n",
"\n",
"an_int = '123'\n",
"no_int = '123abc'\n",
"\n",
"%timeit string_is_int(an_int)\n",
"%timeit string_is_int(no_int)\n",
"%timeit an_int.isdigit()\n",
"%timeit no_int.isdigit()\n",
"\n",
"#\n",
"# Python 3.4.0\n",
"# MacOS X 10.9.2\n",
"# 2.5 GHz Intel Core i5\n",
"# 4 GB 1600 Mhz DDR3\n",
"#"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"1000000 loops, best of 3: 401 ns per loop\n",
"100000 loops, best of 3: 3.04 \u00b5s per loop"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"10000000 loops, best of 3: 92.1 ns per loop"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"10000000 loops, best of 3: 96.3 ns per loop"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n"
]
}
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"prompt_number": 5
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{
"cell_type": "markdown",
"metadata": {},
"source": [
"<br>\n",
"<br>\n",
"<a name='is_number'></a>\n",
"## Testing if a string is a number"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import timeit\n",
"\n",
"def string_is_number(a_str):\n",
" try:\n",
" float(a_str)\n",
" return True\n",
" except ValueError:\n",
" return False\n",
" \n",
"a_float = '1.234'\n",
"no_float = '123abc'\n",
"\n",
"a_float.replace('.','',1).isdigit()\n",
"no_float.replace('.','',1).isdigit()\n",
"\n",
"%timeit string_is_number(an_int)\n",
"%timeit string_is_number(no_int)\n",
"%timeit a_float.replace('.','',1).isdigit()\n",
"%timeit no_float.replace('.','',1).isdigit()\n",
"\n",
"#\n",
"# Python 3.4.0\n",
"# MacOS X 10.9.2\n",
"# 2.5 GHz Intel Core i5\n",
"# 4 GB 1600 Mhz DDR3\n",
"#"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"1000000 loops, best of 3: 400 ns per loop\n",
"1000000 loops, best of 3: 1.15 \u00b5s per loop"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"1000000 loops, best of 3: 452 ns per loop"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n",
"1000000 loops, best of 3: 394 ns per loop"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
"\n"
]
}
],
"prompt_number": 6
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"<br>\n",
"<br>\n",
"<a name='list_operations'></a>\n",
"# List operations"
]
@ -620,6 +790,14 @@
"### Conclusion\n",
"Interestingly, the `try-except` loop pays off if we have more elements (here: 1000 integers instead of 100) as dictionary keys to check. Also, it doesn't matter much whether the elements exist or do not exist in the dictionary, yet."
]
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