Understanding "help" command description syntax - explanation needed
webmailgroups at gmail.com
Wed Nov 5 12:00:16 CET 2014
I'm a Python beginner and just getting familiar with it. (I need it for my
EE B.Sc. project)
For the learning purposes I use IDLE and (Learning Python by written by Mark
Let's say that I have some earlier experience with C language, but still
Python is a different one )))
Anyway, the question I would like to ask is about understanding "help"
It may look to obvious and even a dumb question, but still I need your help.
Here is a brief background with example in order to introduce my problem in
more clear way:
Suppose I get some list created:
>>>L=[i for i in range(1,15,2)]
As it can be seen, this is the odd numbers list: [1, 3, 5, 7, 9, 11, 13]
Supppose I need to check the occurrence of number 7, in this case I'll just
The result is :3
So here is the question itself:
If I use the help command to check the "range" command I get this info:
range(stop) -> range object
range(start, stop[, step]) -> range object
As you've seen in my example I used range(1,15,2). But this knowledge I got
from googling a couple of sites.
I still can't understand the "help" command description.
For instance, how do I need to understand that (start,stop[,step]) it's
just a three numbers?
What do those brackets--> [,] mean?
The same about "str.replace" command, where I get this:
S.replace(old, new[, count]) - using this description I can't really
understand how to write the "replace" function parameters.
So I googled it up and found this example in order to get more clear
understanding of command use.
str = "this is string example....wow!!! this is really string"
print str.replace("is", "was")
print str.replace("is", "was", 3)
thwas was string example....wow!!! thwas was really string
thwas was string example....wow!!! thwas is really string
But still how do I know that those "old, new" are the strings and [,count]
just a number?
I mean, it was more naturally(as a baginner) to me to write
str.replace(is,was[,3]) and that's all.
Finally, as for my opinion, this is a lame way to learn "what a command do"
by constantly googling it for examples.
I need to get more familiar with "help", but the main problem, is that I
couldn't find any suitable explanations/tutorials about "help" syntax and
etc. (maybe didn't search well).
Any explanations/links will be greatly appreciated. I need some help for
Thanks in advance,
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