Trouble with negative float values in Python Lists

Question

So i'm trying to work with floats as elements in Python lists but I keep getting this error. I tried making each value a string and then converting it to a float when calling the array to print but that doesn't seem to work either

P1 = [45.100000, ‐65.400000]
print(P1[0])
SyntaxError: invalid character in identifier

Attempt #2

P1 = ["45.100000", "‐65.400000"]
print(float(P1[1]))
ValueError: could not convert string to float: '‐65.400000'

I have a feeling the issues have to do with the negative value in front of the 2nd elements (@ index 1)

I jut copied your code into a python interpreter and it's not working either. I replaced the negative symbol with the one off my keyboard ( - ) and it worked. Are you using the correct negative symbol? — Polymer
– Polymer, Commented Nov 13, 2018 at 0:23

sacuL · Accepted Answer · 2018-11-13 00:23:10Z

2

There is a problem with the hyphen you are using. If you cut and paste the hyphen in your list p1, and check the unicode, it gives:

>>> ord('‐')
8208

Whereas the proper negative or subtraction sign should be:

>>> ord('-')
45

Depending on how you got that list, you either have to figure out why that character got included, or re-type it with the proper Hyphen-Minus

answered Nov 13, 2018 at 0:23

sacuL

51.6k9 gold badges88 silver badges115 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

user1394 · Accepted Answer · 2018-11-13 00:23:06Z

1

I copied your code and ran it, and all I had to do was replace the "-" Seems like you were using a bad character. Try this;

P1 = [45.100000, -65.400000]

answered Nov 13, 2018 at 0:23

user1394

6181 gold badge7 silver badges18 bronze badges

1 Comment

CosmicCat Over a year ago

Yes, that seems to fix the problem -_-

Kevin Fang · Accepted Answer · 2018-11-13 00:26:24Z

1

This is because your - is not a minus sign but a hyphen character:

>>> "‐65.400000".encode('utf-8') # copy from your example
b'\xe2\x80\x9065.400000'

>>> "-65.400000".encode('utf-8') # Replace with my minus
b'-65.400000'

\xe2\x80\x90 is a hyphen character, see here: your hyphen is U+2010 and the hyphen-minus is U+002D

answered Nov 13, 2018 at 0:26

Kevin Fang

2,0124 gold badges18 silver badges33 bronze badges

Collectives™ on Stack Overflow

Trouble with negative float values in Python Lists

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related