Python (programming)

• End of line is marked by line break
• If you want a statement to span several rows (for example, because the code will be very long and unreadable), you can insert a backslash \ at the end of the row. The line break will not be interpreted as such.
• A block is formed by indentation.

help(vtcapp)

help(vtcapp.getwithsql)

In Python, blocks are formed by indentation. This means that all rows belonging to the same level must be indented equally (watch for tabs):

if x ==1:
    y = 2

If a block does not (yet) contain a code, a “pass” must be set as a wildcard.

if x == 1:
    Pass

https://docs.python.org/library/stdtypes.html#comparisons

There are three ways to define strings in Python:

• 'String’
• ”String”
• ”"”String”"”

The string must be closed with the same symbol with which it is opened. Triple strings (“"”) can be any number of rows (e.g. form definitions or , while single and double strings can be one row each:

In the string, the placeholders are defined with curly brackets and with the method .format() passed in a tuple:

”Hi, my name is {} and I’m {} years old.”.format(“Tobias”, 18)

This variant in Python is very neat, since all variables are specified at the end. The string is displayed in its entirety and is not separated by special characters like [+, &].

If you want to output multiple lines of text, for example an address, you can insert a line break with \n.

A string is treated like a list in Python. The individual symbols can be iterated.

receiverStr = '; '.join(receiver)

You can get all the available string functions with the command:

help(str)

If you want to pass a path in Python, you have to be careful because backslashes in Python are used to encode control characters in strings. For example, the path C:\Documentation\temporary documents\.. becomes C:\Documentation emporary documents\.. and is invalid because \t is interpreted as a tab character. There are two ways to solve this problem:

• Either double all backslashes, i.e. 'C:\\Documentation\\temporary documents\\...'. Of course, this can only be done by typing the path “by hand”.
• “raw string,” which does not interpret any control characters. To do this, simply put an r immediately before the path: path = r’C:\documentation\temporary documents\...'.

https://docs.python.org/library/stdtypes.html#string-methods

https://docs.python.org/library/stdtypes.html#string-formatting-operations

Depending on how a value is initialized, it receives a specific data type. For example, the initialization a = 5 is interpreted as an integer. If you want to initialize the number as a float, you must specify a = 5.0 instead.

For information about the different number formats, use the help function:

• help(int)
• help(float)

For an operation with integer values, the result is an integer value:

10 / 4 = 2 (integer value of 2.5)

The same operation with a float value gives the following result:

10.0 / 4 = 2.5

or

float(10) / 4 = 2.5

This means: If one of the values is a float, the result is always output as a float:

1.5 * 7 = 10.5

1.5 * 6 = 9.0 (float value of 9)

The number representation is formatted as follows:

• {:} – symbols for formatting
• 0 – Prefix is 0
• 6 – Length of number
• 2 – quantity of decimal places
• f – Float

'{:06.2f}'.format(555.3)

Result: 555.30

https://docs.python.org/library/stdtypes.html#numeric-types-int-float-long-complex

There are 3 different collection types in Python.

while Len(list)>0:
    print pop()

for entry in list:
    print entry
    del entry

'abc’.index('c')

'Hi, my name is Hans and I’m learning Python.'.count(' ')

xrange returns a list of numbers used primarily in for loops.

xrange(from, to, [step])

Examples of number lists:

xrange(1,3)

• Result: [1,2]

xrange(0,10,2)

• Result: [0,2,4,6,8]

xrange(1,12,3)

• Result: [1,4,7,10]

https://docs.python.org/library/stdtypes.html#sequence-types-str-unicode-list-tuple-buffer-xrange

In Python, there is the if query, the for loop, and the while loop.

if <query>:
    <do>
elif <query>:
    <do>
else:
    <do>

numbers = [1,2,3]
if 1 in numbers:
    print '1 available.'
else:
    print 'not available.'

for <variable> in <liste>:
    <do>

The For loop in Python knows the beginning and end by indentation and therefore does not need a Next.

user = vtcapp.currentlogin()
projectList = editor.evalocl(“myProjects->orderby(code)”)
for project in projectList:
    print projekt.code  # Members are addressed with periods.

for i in xrange(1,11):
    print str(i)  # numbers from 1-10

while <query>:
    <do>

i = 1
while i <= 10:
    print 'The number is {}'.format(i)
    i += 1

In Python, functions are started with the def keyword. The return value is returned with the return keyword. In Python, there is no distinction between function and procedure. Both are called def. The function returns something and the procedure does not.

Def product(a, b):
    return a*b

def getActive(projectlist):
    resList = []
    for project in projectList:
        if project.active:
            resList.append(project)
    return resList

def firstelleActivitaet(project):
    newAkt = vtcapp.createobject(“Activity”)
    newAkt.projekt = project
    newAkt.bearbeiter = project.projectleiter

    # Activities
    vtcapp.showdetailform(newfile)

def activeSplit(projectlist):
    for project in projectList:
        if project.active:
            aktive.append(project)
        else:
            inactive.append(project)
    return (active, inactive) # Tuple of Lists

active, inactive = activeSeparate(projectList)