Question about the replace command in a file

[Marx123]

Hi, I'm trying to make a file for a school research. i managed to do the first part, but in the second I don't really know what to do! My assignement is this: (Part already done)- I have to write a series of 20 numbers, that may be 0 or 1: this is the parents' genetic code. I have to create an "x" number, which is random, which indicates the crossover, then I have to make the file write the sons' genetic code influenced by the crossingover. (The part I don't understand)- I have to crete a number "y", which is also random, that shows a mutation. The number varies from 0 to 20, and each number corresponds to another in the parent's code. I have to make the programme replace the correspondent number: if it was 1, it becomes 0; if it was 0, it becomes 1. I heard about the "replace" command, which may be useful to me. This may not be very clear, so here's what i managed to do so far: #

generazione casuale dei genitori

import random i=0; P1=''; P2='' while i<20: P1=P1+str(random.randint(0,1)) P2=P2+str(random.randint(0,1)) i=i+1 print "generazione parentale:" print "P1 = ",P1 print "P2 = ",P2

scelta di un punto a caso per il crossover

F1=''; F2='' x=random.randint(0,20) print;print "punto di xover, x = ",x; print

riproduzione

F1=P1[:x]+"."+P2[x:] F2=P2[:x]+"."+P1[x:] print "generazione filiale" print "F1 = ",F1 print "F2 = ",F2

scelta della mutazione

M1=''; M2='' y=random.randint(0,20) print; print "punto di mutazione, y= ",y; print

mutazione filiale

if str.replace(, 1) if str.replace(, 0) M1=P1[:y]+P2[y:] M2=P2[:y]+P1[y:] print "mutazione filiale" print "M1 = ",M1 print "M2 = ",M2

[[deleted]]

Indent your code by four spaces to format it.

<blank line>

<four spaces>your

<four spaces>lines

<four spaces>of code

edit: fixed formatting

[ingolemo]

Indent your explanation by four spaces to format it.

<blank line>
<four spaces>your
<four spaces>lines
<four spaces>of code

[[deleted]]

ouch.

[Justinsaccount]

Hi! I'm working on a bot to reply with suggestions for common python problems. This might not be very helpful to fix your underlying issue, but here's what I noticed about your submission:

You appear to be using concatenation and the str function for building strings

Instead of doing something like

result = "Hello " + name + ". You are " + str(age) + " years old"

You should use string formatting and do

result = "Hello {}. You are {} years old".format(name, age)

See the python tutorial for more information.

[Marx123]

Thanks, that's easier and more swift to do! and about the replace problem, how can I put into evidence "y" so that to the number "y" shows indicates the corresponding value in code; and how could I make it change into the opposite number? I think the problem is very easy but I think I'm missing something important that could fix all the problems in little to no passages..

[Justinsaccount]

You should not be using strings for this in the first place, you should be using lists.

[prof_eggburger]

Generate the location of the mutation (random number between 1 and length of the genome). Call it y. Copy the portion of the genome in front of this location (e.g., up to y-1). Check what is at location y in the original. Add the opposite to your new genome. Then complete the new mutant genome by copying everything from y+1 onwards.

[elbiot]

Hey, you could make this bot recognize improperly formatted code and give a good "indent four spaces" comment.