How can I make an array start at subscript 1 instead of subscript 0 in python?
Basically to solve this problem in python.
4 Answers
If you really want to do this, you can create a class that wraps a list, and implement __getitem__ and __setitem__ to be one based. For example:
def __getitem__(self, index):
return self.list[index-1]
def __setitem__(self, index, value):
self.list[index-1] = value
However, to get the complete range of flexibility of Python lists, you would have to implement support for slicing, deleting, etc. If you just want a simple view of the list, one item at a time, this should do it for you.'
See Python Documentation for Data Model for more information on creating custom classes that act like sequences or mappings.
Comments
+1 to Max. Here's something else you could try:
Just add a None at index 0 of your list. This should get you the functionality. You'll just need to remember to snip out the leading None when you pass your list off to MATLAB
Comments
You can use enumerate() method
a = ['a', 'c', 'v', 's']
for i,v in enumerate(a, 1):
print i, v
1 a
2 c
3 v
4 s
1 Comment
Richard Careaga
Actually, enumerate is a class in module builtins, just to be picky.
You can use custom indexes of the fidx module:
import fidx
# create custom type `list1b` from `list`
fidx.add(list, name='list1b')
# add a map for int indexes (i -> i-1)
fidx.list1b.set_index_map(int, lambda _,i: i-1, override=True)
# create your list
b = fidx.list1b([1,2,3])
print(b[1], b[2], b[3]) # (1, 2, 3)
Comments
listand override stuff... 5 minutes messing round withipythonshould help. However how that helps MATLAB/Excel is unclear. Do you really need to write a file conversion script? In that case why not just use the VBA code in the page you linked to? If you do really need to write a python conversion script implementing a 1-based array is not really the right approach.