Python：循环中的if else语句

Question

For each iteration in given script, i am importing a data and computing a variable. for simplicity, i am not including all that stuff and lets say i want to print the ID for each of 25 cases. In whatever way, i place the last statement, it always prints - either all iterations for last data or last iteration for all data.

for data in range(0,5):

    if data==0:
        for iteration in range(0,5):
            # Import some data 
            ID = (data,iteration)

    elif data ==1:
        for iteration in range(0,5):
            # Import some data 
            ID = (data,iteration)

    elif data ==2:
        for iteration in range(0,5):
            # Import some data 
            ID = (data,iteration)

    elif data ==3:
        for iteration in range(0,5):
            # Import some data 
            ID = (data,iteration)           

   elif data ==4:
        for iteration in range(0,5):
            # Import some data 
            ID = (data,iteration)


   ComputedValue = data + iteration                             
   print( 'ComputedValue = %.1d for ID = (%.1d,%.1d)' %(ComputedValue,data,iteration) )

Currently it prints only for 5 cases:

ComputedValue = 4 for ID = (0,4)
ComputedValue = 5 for ID = (1,4)
ComputedValue = 6 for ID = (2,4)
ComputedValue = 7 for ID = (3,4)
ComputedValue = 8 for ID = (4,4)

What changes/modifications to be done, so it prints for all 25 cases? Thanks!! Rachit

Edit: I don't want to print at the end of every for loop as I want to create a vector of computed values (25 values) and plot it with respect to some variable.

Answer 1

You need to put

print( 'ComputedValue = %.1d for ID = (%.1d,%.1d)' %(ComputedValue,data,iteration) )

at the end of every inner for loop (but still inside of the loop, so not on the same line as the for) that it gets printed for every single iteration.

If you do the same stuff for every loop you could also consider to create a function which you call there with the print in it.

To receive a vector with all values in the end insert this line in the beginning (before the outer for loop):

hist = []

Then in every inner for loop add this line:

hist.append(id)

Now you'll have all values available after you're done with the loops and can print them or do whatever you like with them.

Answer 2

I don't want to print at the end of every for loop as I want to create a vector of computed values (25 values)

Well, so why don't you just do that ("create a vector of computed values") then ???

values = []
for i in range(5):
   for j in range(5):
       values.append((i, j))

print(values)

Answer 3

If you want to print after each iteration, without accumulating the result and printing it at the end (like in Bruno's answer) then you can use a simple function like in the following example:

def f(data, r=range(5)):
    for iteration in r:
        ID = (data, iteration)
        print( 'ComputedValue = %.1d for ID = (%.1d,%.1d)' %(ComputedValue,data,iteration) )

for data in range(5):
    f(data)

You can modify the function as you think is best for your code, without the need of writing all that boilerplate code.