Invalid literal for int() with base10

Question

As hard as it is for me to explain my problem, here goes my best:

Im trying to, in a first step, confirm if a certain position of a previously created array is 0 and do replace that 0 with a string. After that I want to confirm if this same position is 0 again and if its not , join the previous string with a new one.

For better understanding I will show a piece of my code:

room1=np.array([["chair","table","book","computer","person"],[0,0,0,0,0]])

The above is the array(or matrix)

if int(room1[1,k])==0:
     room1[1,k]=tipoObjF[1] #tipoObjF[1] being the string I want to replace the 0
else:
     room1[1,k]=room1[1,k]+tipoObjF[1]

Here is where I want to do as I mentioned before: Check if a certain position is 0 and if it is, replace it with a String. Otherwise just join both Strings.

When im running it the following error appears:

ValueError: invalid literal for int() with base10: 'chair1'

I hope I was able to properly explain my problem. This error appears in a project im working on using ROS and chair1 is the first thing that replaces the 0 and is what should be joining in the else statement making it Chair1Chair1 the result im expecting.

Thank you in advance for anyone willing to help

Edit: In the end the array should look as follows:

room1=np.array([["chair","table","book","computer","person"],["chair1chair",0,0,0,0]])

Answer 1

If you attempt to cast room[1,k] to an int after the element has been swapped for a non-integer string, you can't call int() on it any longer. For example, int("chair1chair") throws the error you see.

Because the values may be int or string, you can instead start by comparing string values like:

if str(room[1,k]) == "0": ...

Doing so allows str(0) == "0" to return True but also str("hello") == "0" to return False.