ArcGIS Pro 2.8.4: A python expression fails to perform on “field calculator”,

[JamalNUMAN]

ArcGIS Pro 2.8.4: A python expression fails to perform on “field calculator”,

I couldn’t figure out why the python expression below fails to perform on “field calculator

!A! + "/"+ !B!

This expression is supposed to combine the field A and field B in field C. The first value in the C table when computed is assumed to be 33 / 1

What could be the issue here?

The gdb file is attached

[Luke_Pinner]

The error message is telling you that you can't add a string to a number. The "+" operator is for adding numbers or concatenating strings, not adding or concatenating strings to numbers.

Use string formatting instead:

C = f"{!A!} / {!B!}"

# or 
C = "{} / {}".format(!A!, !B!)

# or
C = "%s / %s" % (!A!, !B!)

[JohannesLindner]

A and B are floats, "/" is a string.

In Python, addition between float and str isn't defined, so the Field Calculator doesn't know what to do.

You have to convert the floats to strings using one of these methods:

# explicitly cast the floats to strings
str(!A!) + "/" + str(!B!)

# implicitly cast to string with str.format()
"{}/{}".format(!A!, !B!)

# implicitly cast to string with format string
f"{!A!}/{!B!}"

[JamalNUMAN]

The expression (str(!A!) + "/" + str(!B!)) adds one decimal number for each number.

How to eliminate this decimal number?

[Luke_Pinner · Accepted solution]

Again, use string formatting

f"{!A!:.0f} / {!B!:.0f}"

"{:.0f} / {:.0f}".format(!A!, !B!)

"%.0f / %.0f" % (!A!, !B!)

[JoshuaBixby]

You are making it harder than it has to be.  Just don't wrap your Python division character in a string.  For example:

!A! / !B!

[Luke_Pinner]

@JoshuaBixby then will the result be the division of the two numbers (not what OP wants) instead of a string with the two numbers separated by a forward slash (what the OP wants)?

[JoshuaBixby]

@Luke_Pinner, I was too quick skimming over the question, thanks for pointing out the real question.

[JamalNUMAN]

Thank you for the help. It works fine