Learning python, lost with script

Applications Programming
1

Hi there,

im just having a hard time understanding why this code does not print anything that is suppose to print:

score = raw_input ('what is your score? \n')

try:

        if 1.0 == float(score) >= 0.9:
            print "A"

        elif 0.9 > float(score) >= 0.8:
            print "B"

        elif 0.8 > float(score) >= 0.7:
            print "C"

        elif 0.7 > float(score) >= 0.6:
            print "D"
    
        elif 0.6 > float(score):
            print "F"


except:

            print "bad score"

whereas this other one does do the job correctly:

score = raw_input ('please provide a score between 0.0 and 1.0\n')

try:

    if float(score) >= 0.9 and float(score) <= 1.0:

        print "A"  

    elif float(score) >= 0.8 and float(score) < 0.9:

        print "B"

    elif float(score) >= 0.7 and float(score) < 0.8:

        print "C"

    elif float(score) >= 0.6 and float(score) < 0.7:

        print "D"

    elif float(score) < 0.6:

        print "F"

except:
    print "Bad score"

Any insight?

---------- Post updated at 08:55 AM ---------- Previous update was at 08:44 AM ----------

Ok, I got it, the right way to define a numerical range is as in the second option. But why then I dont get any error if the first code is not written properly?

2

Because for python it's a perfectly valid expression.

When you say, 1.0 == float(score) >= 0.9 ,
python understands it as 1.0 == float(score) and float(score) >= 0.9
which will always evaluate to false unless score is 1.0