Differences between revisions 10 and 20 (spanning 10 versions)

For loops

a)

   1 for i in range(0,4,1):
   2      print i
   3 
   4 0
   5 1
   6 2
   7 3

Insert an expression in ... to get the results.

Solution:

b)

What are the corresponding loops?

Solution:

In [51]: a='0' In [52]: b='1' In [53]: 4*a+4*b

Out[53]: '00001111'

In [44]: a=0,1,2,3

In [45]: a*4

Out[45]: (0,1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0)

Second Solution (in einer Schleife):

a = [range(0,4)]

for item in a:

b = item * 4 b.sort() c = item * 4 d = [b,c] print d

Data types

A=dict([('a',1),('b',2)])

Please specify the data types:

A is a ...
'a' is a ...
1 is a ...
('a',1) is a ...
[('a',1),('b',2)] is a ...

Provide an alternative way to assign A

Scipy numeric types

from scipy import *

One byte consists of eight bit and covers the value range of 0..255 (uint8, unsigned integer) or -128..127.

   1 b=int8(128)
   2 -128 # Invalid range
   3 
   4 b.nbytes
   5 1

a)

What is the value range of the following types and how many bytes are allocated in the memory?

bool8
uint8, int8
uint16, int16
uint32, int32
uint64, uint64

Solution:

b)

How many bytes are allocated in the memory by these floating point types?

float32, float64, float96
complex64, complex128, complex192

Solution:

Data structures

a)

   1 D={'A':array(range(10)),'B':array(range(10))+1}

Which keys contains the dictionary D
Get the keys with the method D.keys()
Display all values of D using the method .values()
Display array A
Display the elements 3:6 of arrays B
Set this elements to 0
Insert a new key-values pair C:array(range(0,10,-1)) into D

Solution:

Reading and practicing

Install python and ipython on your computer and read through the tutorial which comes with the documentation. There are translations in other languages:

-  ⇤ ← Revision 10 as of 2008-11-10 13:56:15 → 
  Size: 2352
  Editor: anonymous
  Comment:
+   ← Revision 20 as of 2008-11-17 14:13:28 → ⇥
  Size: 2727
  Editor: KorFreier
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 5:
+= For loops =
== a) ==
{{{
#!python
-Line 6:
+Line 10:
+for i in range(0,4,1):
     print i
-Line 7:
+Line 13:
-= For loops =

== a) ==

{{{#!python
for ...:
     print i
-Line 16:
+Line 14:
-Line 20:
+Line 18:
-Line 44:
+Line 41:
-Line 49:
+Line 45:
+In [51]: a='0'
In [52]: b='1'
In [53]: 4*a+4*b

Out[53]: '00001111'
-----

In [44]: a=0,1,2,3

In [45]: a*4

Out[45]: (0,1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0)

Second Solution (in einer Schleife):

a = [range(0,4)]

for item in a:<br>
         b = item * 4 <br>
         b.sort()<br>
         c = item * 4<br>
         d = [b,c]<br>
         print d <br>
-Line 50:
+Line 72:
-Line 54:
+Line 75:
-Line 57:
+Line 77:
-Line 65:
+Line 84:
-Line 68:
+Line 86:
-Line 71:
+Line 88:
-One byte consists of eight bit and covers the value range of 0..255 ({{{uint8}}}, unsigned integer) 
or -128..127.
+One byte consists of eight bit and covers the value range of 0..255 ({{{uint8}}}, unsigned integer)  or -128..127.
-Line 74:
+Line 90:
-{{{#!python
+{{{
#!python
-Line 81:
+Line 99:
-Line 83:
+Line 100:
-Line 94:
+Line 110:
-Line 96:
+Line 111:
-Line 106:
+Line 120:
-{{{#!python
+{{{
#!python
-Line 109:
+Line 125:
-Line 114:
+Line 129:
  * Display the elements {{{3:6}}} of arrays {{{B}}}
-Line 116:
+Line 131:
  * Insert a new key-values pair {{{C:array(range(0,10,-1))}}} into {{{D}}}
-Line 120:
+Line 135:
+= Reading and practicing =
Install python and ipython on your computer and read through the tutorial which comes with the documentation. There are translations in other languages:
-Line 121:
+Line 138:
-= Reading and practicing =

Install python and ipython on your computer and read through the tutorial which comes with the documentation. There are translations in other languages: