Understanting what the syntax for {:.2} means in python

Question

I am working on creating a linear regression model for a specific data set, I am following an example I found on you tube, at some point I calculate the kurtosis and the skewness as below:

# calculate the excess kurtosis using the fisher method. The alternative is Pearson which 
calculates regular kurtosis.
exxon_kurtosis = kurtosis(price_data['exxon_price'], fisher = True)
oil_kurtosis = kurtosis(price_data['oil_price'], fisher = True)

# calculate the skewness
exxon_skew = skew(price_data['exxon_price'])
oil_skew = skew(price_data['oil_price'])

display("Exxon Excess Kurtosis: {:.2}".format(exxon_kurtosis))  # this looks fine
display("Oil Excess Kurtosis: {:.2}".format(oil_kurtosis))      # this looks fine

display("Exxon Skew: {:.2}".format(exxon_skew))          # moderately skewed
display("Oil Skew: {:.2}".format(oil_skew))              # moderately skewed, it's a 
little high but we will accept it.

I am new to python, and the following code confuses me here {:.2}, please can someone explain what this part {:.2}

display("Exxon Excess Kurtosis: {:.2}".format(exxon_kurtosis))

A floating point with 2 significant figures. – Aplet123 Dec 26 '20 at 14:40 — Aplet123, Dec 26 '20 at 14:40
https://docs.python.org/3/library/string.html#formatspec – Håken Lid Dec 26 '20 at 14:46 — Håken Lid, Dec 26 '20 at 14:46

ti7 · Accepted Answer · 2020-12-26T14:48:31.333

4

The kurtosis and skew functions are doing the calculation, while the display function is probably just some form of print() for that environment!

".. {:.2}".format(x) is a string formatter which rounds floating points to 2 significant digits

>>> "{:.2}".format(3.0)
'3.0'
>>> "{:.2}".format(0.1555)
'0.16'
>>> "{:.2}".format(3.1555)
'3.2'

String formatting is exhaustively detailed here

edited Dec 26 '20 at 14:48

answered Dec 26 '20 at 14:42

ti7

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Understanting what the syntax for {:.2} means in python

1 Answers1