How to print out n (3) items from a list at a time and then display them on one line. Python 3

Question

As you can see from the code below, I have my program read text from a text file (homework.txt) to a list called heightandweight. I then have it print 3 items in the list at a time. However it doesn't print the 3 pieces of information on one line. How would I do that?

myFile = open("homework.txt","rt")
heightandweight = []

for line in myFile:
    line = line.strip("\n")
    heightandweight.append(line)

print(heightandweight)
myFile.close()

for e in range (0, len(heightandweight),3):
    for i in heightandweight[e:e+3]:
        print (i)

The above code will output:

['James', '73', '1.82', 'Peter', '78', '1.80', 'Jay', 'Beth', '65', '1.53', 'Mags', '66', '1.50', 'Joy', '62', '1.34']
James
73
1.82
Peter
78
1.80
Jay
Beth
65
1.53
Mags
66
1.50
Joy
62
1.34             

Answer 1

You probably need to learn about formatting strings in python. In your case the relevant code would be something like:

for e in range (0, len(heightandweight),3):
    string="{} {} {}".format(heightandweight[e], heightandweight[e+1], heightandweight[e+2])
    print(string)

Which could be compressed into just:

for e in range (0, len(heightandweight),3):
    print("{} {} {}".format(heightandweight[e], heightandweight[e+1], heightandweight[e+2]))

However it would be much neater to have the original text file be organised like this in columns:

James 73 1.82
Peter 78 1.80
Beth 65 1.53
Mags 66 1.50
Joy 62 1.34

Then your code could be simplified to:

with open("homework.txt","rt") as myFile:
    for line in myFile:
        name, height, weight = line.split(' ')
        print("{} {} {}".format(name, height, weight))

Answer 2

If you don't want to use format strings (ie if you just want to print out a set of data without having a newline) then you can prevent a newline by using:

print data,

or, if you're using Python 3:

print(data, end="")

Assuming the latter, your code would then look like:

for e in range (0, len(heightandweight),3):
    for i in heightandweight[e:e+3]:
        print(i, end="")
    print("")

Answer 3

With python it is very easy. I recommend you strongly to check the function join ( https://docs.python.org/3/library/stdtypes.html#str.join ).

I am not sure if this is why you want but you can test this :

for e in range (0, len(heightandweight),3):
    print(" ".join(heightandweight[e:e+3]))

Answer 4

simple iterator:

lst=['James', '73', '1.82', 'Peter', '78', '1.80', 'Jay', 'Beth', '65', '1.53', 'Mags', '66', '1.50', 'Joy', '62', '1.34']
lst_copy=lst #if You need to use oryginal lst later use it, otherwise dont
for i in range(len(lst)):
    try:lst[i]=float(lst[i])
    except:pass
for i in range(0,len(lst),3):
    try:
        if type(lst_copy[i+1])!=float:
            print(lst_copy[i])
            lst_copy.pop(i)
        else:
            print(i,lst_copy[i:i+3])
    except:pass